Amended September 7, 2016 Kathryn Winger and Timothy Potts v. Cm Holdings, L.L.C. ( 2016 )

  •                IN THE SUPREME COURT OF IOWA
                                  No. 14–0199
                              Filed June 24, 2016
                          Amended September 7, 2016
          On review from the Iowa Court of Appeals.
          Appeal from the Iowa District Court for Polk County, Richard G.
    Blane II, Judge.
          Plaintiffs and defendant seek further review of court of appeals
    decision ordering a new trial in a wrongful-death action arising from a
    fatal fall from an apartment balcony.       DECISION OF COURT OF
          Robert G. Rehkemper and Cory F. Gourley of Gourley, Rehkemper
    & Lindholm, P.L.C., for appellants.
          Brenda K. Wallrichs of Lederer Weston Craig PLC, Cedar Rapids,
    and Michael A. Carmoney and Jack W. Leverenz of Carmoney Law Firm,
    PLLC, Des Moines, for appellee.
    WATERMAN, Justice.
          This wrongful-death action arises from a fatal fall from an
    apartment balcony and presents several issues on the applicability of the
    doctrine of negligence per se to an alleged municipal housing code
    violation.   The thirty-two-inch high balcony railing complied with the
    local housing code when the apartment complex was constructed in
    1968, but unless exempted under a grandfather provision, it is ten
    inches shorter than the current housing code allows.                   Before the
    accident, a local housing inspector cited the landlord for that code
    violation.   The inspector reasoned that an attached plastic lattice
    modified the railings to eliminate grandfather status. The landlord did
    not appeal that finding but rather ordered the higher railings and asked
    for an extension of time to install them. The City of Des Moines Housing
    Appeal Board (HAB), without a contested hearing, found the property
    was in violation but granted a three-month extension to install compliant
    railings and suspended the $1090 fine. The plaintiffs’ daughter fell over
    the original railing to her death three days later.
          The plaintiffs filed a premises liability action alleging the thirty-
    two-inch railing violated the local housing code. Their expert testified the
    forty-two-inch railing would have prevented the accident.              The district
    court ruled the landlord was bound by the HAB’s determination that
    forty-two-inch   railings   were   required   and     rejected   the     landlord’s
    arguments that the property was grandfathered out of the current code
    or that the HAB’s extension of time to install higher railings excused tort
    liability. The court instructed the jury that the landlord’s violation of the
    housing code constituted negligence per se and limited the jury to
    deciding causation, comparative fault, and damages. The jury found the
    landlord sixty-five percent at fault, the plaintiffs’ daughter thirty-five
    percent at fault, and awarded combined total damages of $1,750,000
    ($1,137,500 after reduction for comparative fault). In posttrial rulings,
    the district court concluded the doctrine of negligence per se did not
    apply to a local housing code and ordered a new trial.           Both sides
    appealed, and we transferred the case to the court of appeals, which
    affirmed with one judge dissenting and another specially concurring. We
    granted the applications for further review by both sides.
          For the reasons explained below, we hold that the doctrine of
    negligence per se applies to the violation of a municipal housing code
    and is not limited to statewide laws.       Additionally, the district court
    correctly rejected the landlord’s argument that the old code applied as a
    matter of law. The HAB’s extension of time for the landlord to comply
    with the code merely suspended administrative penalties without
    excusing tort liability. The district court, however, erred by instructing
    the jury on the basis that the new code applied as a matter of law. The
    HAB’s determination of a code violation does not have preclusive effect in
    this wrongful-death action.       On remand, the parties may present
    evidence on whether prior modifications eliminated grandfather status.
    Accordingly, we vacate the decision of the court of appeals, reverse the
    district court’s posttrial rulings, and remand this case for a new trial.
          I. Background Facts and Proceedings.
          On July 23, 2011, twenty-one-year-old Shannon Potts came to the
    Grand Stratford Apartments in Des Moines after work to socialize with
    friends. She arrived at their second-floor apartment around 1:30 a.m.
    slightly intoxicated and watched movies with a small group.                 She
    continued drinking until about 4 a.m. when her friends hid the alcohol.
    Shannon asked one to talk with her privately on the balcony.            They
    talked for about twenty minutes before her friend returned inside to get
    another drink.   While inside, her friend heard a scream and a crash.
    Shannon had gone over the railing.          Her friends ran downstairs and
    found her unresponsive. A bystander called 911. Shannon was rushed
    to the hospital with a fractured neck and crushed spine and was
    pronounced dead there. Toxicology tests indicated she was intoxicated
    at the time of her fall and had marijuana and Xanax in her bloodstream.
          Mark Critelli was the sole owner of the Grand Stratford Apartments
    until February 15, just over five months before Shannon’s fatal fall. This
    apartment complex consists of a duplex and three larger buildings
    constructed in 1968. The apartments were built to comply with the 1968
    housing code, which required guardrails between thirty- and thirty-four
    inches high. Des Moines, Iowa, Municipal Code § 24-28.06 (1962). The
    original black iron railings are thirty-two inches high and remained in
    place when Shannon fell forty-three years later.            In 1979, the
    Des Moines, Iowa, Municipal Code was amended to require guardrails of
    forty-two inches in height. Des Moines, Iowa, Municipal Code § 14-10(b)
    (1979).   The 1979 code included a grandfather provision stating that
    “[g]uardrails which were installed prior to the passage of this subchapter
    and were in conformance with the Health and Safety Housing Code then
    in effect may be allowed to remain if in structurally sound condition.” Id.
    In 2005, the guardrail ordinance stated, “Multiple family dwellings with
    porches, balconies or raised floor surfaces located more than 30 inches
    above the floor or below grade shall have guards not less than 42 inches
    in height.” Des Moines, Iowa, Municipal Code § 60-127(c) (2005). The
    grandfather provision was revised to state, “Any structure that was in
    compliance on the day previous to the adoption of this code will be
    allowed to remain.”     Id. § 60-5.       The ordinance was admitted into
    evidence without objection.
          The HAB found Critelli was a “habitual violator” of the code. All
    properties under his ownership were put on an accelerated inspection
    schedule. In 2009, Critelli attached a forty-eight-inch high white plastic
    lattice to the guardrails with zip ties.   The lattice served as a privacy
    screen to shield each balcony from view.        Although Critelli received
    numerous notices of violations regarding this property, none addressed
    the guardrails before February 2011.
          Eddie Leedom is a city inspector assigned to the Neighborhood
    Inspection Unit.    He inspected the Grand Stratford Apartments on
    February 10 and found 106 code violations, including the guardrail
    height, broken window screens, and a broken garbage disposal. Leedom
    concluded the plastic lattice was an alteration to the guardrails that
    triggered a duty to comply with the current forty-two-inch guardrail
    requirement.   He spoke with the director of the HAB who agreed the
    thirty-two-inch guardrails were too low.
          On February 15, Eric Estes and Merle Laswell formed CM Holdings
    with Mark Critelli to acquire a controlling ownership interest in the
    Grand Stratford Apartments.        The property was in disrepair, and
    CM Holdings began renovating the apartments to increase their rental
    value. As part of their renovation plan, the new owners vacated two of
    the apartment buildings but permitted tenants to remain in the third.
    Estes and Laswell planned to allow tenants to move from the
    unrenovated building into the newly renovated buildings as upgrades
    were completed.
          Estes received the notice of violations on February 24.           The
    violations were not prioritized, so Estes gave the list of violations to his
    general contractor without identifying which violations to address first.
    By March 31, CM Holdings had fixed fifty-eight violations.          On an
    inspection on July 5, Leedom noted only six remaining violations.         He
    imposed a $1090 fine for the guardrail-height violations. By July 13, the
    only remaining infraction was the height of the guardrails, and
    CM Holdings had ordered new forty-two-inch guardrails.
          After each inspection, Leedom sent CM Holdings a notice listing
    the violations and the remedial action required. Each notice contained a
    notification of the right to appeal the inspection, stating,
          APPEALS: Under section 60-102(a)
                 (1)    Any owner objecting to a violation cited in this
                        Inspection Notice may file a written appeal with
                        the Neighborhood Inspection Division requesting
                        a hearing before the Housing Appeals Board. An
                        appeal shall be filed within 10 days of the date of
                        the Inspection Notice. Upon the discretion of the
                        Neighborhood Inspection Officer for good cause
                        shown, an untimely appeal may be accepted.
          At this hearing the appellant shall have the opportunity to be
          heard, the right to call witnesses and to be represented by
    CM Holdings never appealed any of the notices of violation.
          On July 13, ten days before the accident, Estes and Laswell
    appeared on behalf of CM Holdings at a regularly scheduled HAB meeting
    to request an extension of time to bring the property into compliance and
    to suspend the $1090 fine.        CM Holdings was one of four property
    owners present requesting extensions at the monthly meeting, and all
    received extensions.     Leedom and the HAB members applauded the
    progress CM Holdings had made on improving the properties. A board
    member asked if they could restrict access to the balconies until higher
    railings were installed, and Estes replied that he did not know. Estes
          [T]he only reason they are not in compliance is because of
          the height. The code has changed. I mean they are all in
          good shape and they are, you know they’re functional. . . .
          [W]e have ordered all new railings for it.
    Estes told the board that CM Holdings wanted to replace the decking and
    patio doors on the twelve units at issue at the same time, which would
    take fifteen days after the materials arrived.      He also stated, “[The
    guardrails] are all in good condition. They’re just not the right height.” A
    board member replied,
          Obviously, these folks are doing what they need to do to get
          this taken care of, but, you know, I don’t want my name
          associated with the kid that falls off the balcony because the
          railings aren’t the right height.
    Estes admitted the guardrail height was a health and safety issue but
    reminded the board that the guardrails had been at that height for forty-
    five years without an accident.    The board granted CM Holdings until
    October 7 to fix the violation. Neither the board nor CM Holdings raised
    the issue of whether the existing guardrails were grandfathered under
    the housing code.
          The HAB issued a notice of its decision on July 20, stating,
                 The above referenced property has been found to be in
          violation of the Municipal Code of the City of Des Moines,
          Iowa. The property was not brought into compliance as
          ordered by the Notice of Violation issued by the
          Neighborhood Inspection Division. The case was referred to
          the Housing Appeals Board (HAB) and the Board ordered the
                 The HAB granted an extension until 10-07-2011 to
          complete the repairs and suspended the $1,090.00 fine.
          However, the board also made a part of that motion that if
          repairs are not completed by the same date, this case will be
          referred to the Legal Department for prosecution.
    Shannon Potts fell over the balcony rail to her death three days later.
          On June 19, 2012, Shannon’s parents, Kathryn Winger, the
    executor of Shannon’s estate, and Timothy Potts (the plaintiffs) filed a
    lawsuit on behalf of Shannon’s estate and for loss of consortium.         On
    September 5, 2013, CM Holdings moved for summary judgment on the
    ground that the extension from the HAB to install higher guardrails was
    a legal excuse precluding tort liability. On September 26, the plaintiffs
    moved for partial summary judgment on the ground that the violation of
    the forty-two-inch guardrail requirement constituted negligence per se as
    a matter of law. CM Holdings resisted the plaintiffs’ motion on several
    grounds: the HAB extension, the grandfather clause, and a legal
    argument that the doctrine of negligence per se does not apply to a local
    ordinance.    The district court deferred ruling on the cross-motions for
    summary judgment until trial.
          The jury trial began on November 4, 2013, and lasted five days.
    Housing inspector Leedom testified as follows regarding housing code
                Q. Safety codes periodically change over time; is that
          true? A. That’s true.
                Q. Do you know when that apartment was originally
          built? A. No, I don’t.
                Q. Do you know if those 32-inch guardrails complied
          with the building code that may have existed when the
          building was originally built? A. I have to assume that they
          did. It would have to be inspected then.
                Q. Now, as a general proposition, if the code changes,
          does that automatically mean that everybody has to go
          immediately update their property? A. No.
                Q. And, in fact, if a code changes, absent any other
          circumstances, does a property remain compliant so long as
          it was compliant with the previous code? A. Yes.
                Q. What circumstances can arise that require a
          property owner to bring an older property up into compliance
          with a new code? A. If a portion of that property were to be
          decayed, defective to the point that it has to be replaced; or if
          that portion of the property had been altered in any way that
          did not meet the code of today.
                Q. Explain what type of alterations trigger a
          requirement that a property owner bring a particular
          building up to compliance. A. If someone makes an addition
          to a piece of property or if someone takes something away
          from it, anything that they might do to change the way it is
          used and a safety factor of it.
                 Q. So if a particular part of a building has its use or
          its safety changed, then that can be one of those alterations
          that trigger the property owner to bring the building into
          compliance with the current code? A. Yes.
                 Q. Did that happen with respect to 531 35th Street?
          A. Yes.
                 Q. Explain that for the jury. A. The guardrails on the
          balconies at 531 had been altered, and the fact that they had
          — they’d put latticework attached to the guardrails to raise
          the height of the guardrail, and the extended height was
          nothing but latticework.
                 That made an alteration in the way it looked, it made
          an alteration in the way it was used, and it made an unsafe
                 Q. Explain how you felt that addition of the
          latticework could be unsafe for someone that would have
          been standing on that deck or balcony.           A. Well, the
          additional height that was made by putting the latticework
          there, the latticework was not a material that would be
          strong enough to be used as a guardrail. It was just flimsy.
          The plaintiffs introduced pictures of the latticework. The plaintiffs
    then questioned Leedom regarding why the latticework was an alteration.
                Q. That difference in height was one of the problems
          that you felt required the change and the alteration of this
          property to be brought in compliance with the Des Moines
          Housing Code? A. Yes.
    Leedom testified the property was in violation of the city ordinance.
                Q. [T]he guardrail was at 32 inches; the latticework
          went up above that? A. Correct.
                 Q. On July 23, 2011, was CM Holdings, L.L.C.,
          violating the law in that respect with respect to that
          property? A. I can say they were in violation of the city
          ordinance, yes.
          CM Holdings cross-examined Leedom about which code provisions
    applied to the Grand Stratford Apartments:
                Q. As far as you know, all of the components of this
          building were in full compliance with the building and the
          housing codes that would have been in effect back at that
          time in 1968? A. Yes.
                Q. Back then 32-inch guardrails would meet the code
          at that time? A. Probably, Yes.
          Q. Housing and building codes do change over time.
    You talked about that? A. Yes.
          Q. The height requirement for guardrails on new
    construction today is 42 inches in height? A. Correct.
          Q. Now, you acknowledged earlier that under the law
    that owners of existing property are not required to bring
    their building up to code every time that code changes?
    A. That’s correct.
           Q. As a general rule? A. Yes.
           Q. As a general rule, as long as the building is in
    compliance with the existing code on the day before the
    change takes place, then the building is deemed to be in
    compliance right on through; correct? A. Yes.
           Q. We call that routinely grandfathered in? A. That’s
    what it’s called, yeah.
           Q. If I look at the first paragraph there [of the
    Des Moines Municipal Housing Code section 60-5], the very
    last sentence of that first paragraph, I’m just going to read it,
    if you could follow along and confirm I’m reading it correctly.
           “Any structure that was in compliance on the day
    previous to the adoption of this code will be allowed to
    remain.” Did I read it correctly? A. Yes.
           Q. That’s the grandfather clause; right? A. That’s
    what it’s called. That’s the laymen’s term, yes.
           Q. [Y]ou never indicated any specific reason for the
    requirement that those railings be upgraded to the current
    code, not in those written reports; correct? A. Just the
    height requirement.
           Q. You indicate the height requirement but never
    indicated a reason why the new 42-inch requirement would
    be triggered? A. No.
           Q. You stated that it was the attachment of that
    plastic lattice to the rails themselves that you feel triggered
    the requirement to bring the railings up to the current code?
    A. Yes.
          Q. The guardrails themselves—and here I’m talking
    about the actual metal guardrail that provides protection for
    people who go on the balconies—those guardrails were never
    actually modified by putting the lattice in place.
           It added an additional, just trying to—adding those
    plastic lattice pieces didn’t change the guardrails themselves;
    right? A. It gave the perception of a higher guardrail.
                Q. But it didn’t actually change the              physical
          properties of the metal rails themselves? A. No.
                 Q. Now, when you walk out on one of these balconies
          and you look at the guardrail with the lattice attached, the
          lattice would be on the outside of the railings; right? A. I
          believe it was.
                Q. The view of the actual railing is not blocked per se
          by the lattice? A. The view of the iron is not, no. It’s not
          covered up.
                Q. In any event, this particular issue that you found
          was never specifically identified on the inspection notices.
          You simply indicated that the new height requirement of 42
          inches was in effect? A. Yes.
          On redirect, the plaintiffs probed how Leedom concluded that it
    was an alteration.
                Q. There    was     some    discussion  about     your
          determination that the latticework was a change of use of the
          guardrails with [CM Holdings’ counsel]. Do you recall that
          discussion? A. Yes.
                Q. Was it the change of effect that you felt that might
          have on the perception of someone out there in terms of their
          safety that caused you to call it a change of use? A. Yes.
          You could see that the latticework is being broken and
          busted off above the original iron guardrail.
                 Q. And, once again, did you state that that felt to you
          like a false sense of security for someone that was out there
          with that latticework around there? A. Yes.
                 Q. After you made the determination that adding the
          latticework to the guardrail was a change of use, did you talk
          to anybody else about that determination? A. Yes.
                Q. Who did you talk to? A. I talked to my supervisor.
               Q. Who was        your   supervisor   back    in     2011?
          A. Jack Hanson.
                Q. And what position did he hold at or for the City
          back in 2011? A. He agreed that it would be an alteration of
          the handrail—or guardrail. I’m sorry. Guardrail.
    The chairman of the HAB, Richard Bason, testified about the grandfather
               Q. [D]o you recall whether or not the railings were
          compliant with the Des Moines Code? A. No. That’s why
          [Leedom] brought them before the board. They were not in
          compliance from the standpoint of — as I recall, at the
          original time that Mr. Leedom inspected the property they
          were found to be — there was something added. They were
               And therefore, because of that, he faulted the property
          because of this change, whether it was a latticework or
                Prior to that it had passed code, I believe, many times
          —inspection. It passed inspection. But it’s not uncommon
          that when different inspectors go out, just because it passed
          the last four times doesn’t mean that he didn’t catch it this
                But the case here is the fact that it was changed. The
          uses of it had been changed, modified. And that was, I
          believe, the main reason he faulted it as being then —
          because it was changed, it eliminated the grandfather in his
          mind. And, therefore, he was bringing it and saying, Okay,
          we got to make it to current code. That’s the best I can
          remember on it.
          The plaintiffs’ expert, Richard Hinrichs, a professor at Arizona
    State University, testified regarding why guardrails are required to be
    forty-two inches high:
                 The International Building Code is based on—that they
          arrived at the 42-inch minimum height based on where the
          average person’s center of gravity falls when standing. And
          I’m sure that there was originally research done in order to
          arrive at that height of 42 inches.
                 But essentially if you have a 42-inch-high guardrail,
          for the vast majority of people, except for the tallest
          individuals, that 42 inches will be above the height, the
          standing height, of one’s center of gravity.
                 And if you have something that’s above the center of
          gravity, you’re less likely to fall over it than if something is
          below the center of gravity. There’s something very important
          about that point that we call the center of gravity and how
          high it is relative to the top of the guardrail.
          CM Holdings proposed a jury instruction in pretrial submissions
    stating that if the jury found the apartments were grandfathered out of
    the guardrail requirement, it would not be negligent 1 and another
    proposed instruction regarding legal excuse based on the HAB’s
    extension of time to correct the violations. 2 At trial, the plaintiffs moved
    for a directed verdict on liability, and CM Holdings moved for a directed
    verdict on two grounds: legal excuse based on the HAB extension and the
    grandfather provision.        The district court denied CM Holdings’ motion
    and granted the plaintiffs’ motion, ruling that the failure to install forty-
    two-inch railings constituted negligence per se.
          During the jury instruction conference, CM Holdings did not reoffer
    the proposed jury instructions regarding the grandfather clause or legal
    excuse.   The court, over CM Holdings’ objection, gave instruction 15,
    which stated,
          You are instructed that the Court has determined as a
          matter of law that pursuant to the Des Moines Municipal
          Housing Code the Defendant was required before July 23,
          2011, to install guardrails that were at least 42 inches in
          height on the balcony of Apartment No. 9 at 531–35th Street
          Des Moines, Iowa.
          1The   proposed instruction stated,
          The Des Moines Housing Code contains the following provision in respect
          to multi-family dwellings:
                   Section 60-5. Scope, applicability and exceptions.
                           Any structure that was in compliance on the day previous
                   to the adoption of this code will be allowed to remain.
                   If you find that the Des Moines Housing Code Sec. 60-5 applied to
                   [the Grand Stratford Apartments] on July 23, 2011, you must
                   find the defendant was not in violation of the Des Moines Housing
                   Code Section 60-127, and was not negligent as alleged in part ___
                   of Instruction No. ____.
          2That   proposed instruction stated,
          If you find that Defendant CM Holdings had a valid extension of time
          issued by the City of Des Moines Housing Appeals Board to repair the
          guardrails that was in effect on July 23, 2011, you must find that
          defendant was not negligent as alleged in part ___ of Instruction No. ____.
                Defendant’s violation of law is negligence as to
          Instruction No. 16.
    CM Holdings objected to this negligence per se instruction as follows:
                 At this point, based upon the rulings of the Court, that
          verdict form appears to — although Defendant disagrees
          with the ruling, it appears that the verdict form is set up in a
          manner that doesn’t unfairly highlight that issue [the
          violation of the municipal housing code] yet again. . . .
                [W]ith regard to the verdict form and more as a general
          matter, Defendant does object and would urge the Court to
          reconsider its ruling on the legal issues regarding its finding
          that there was a violation of the Municipal Housing Code.
                Defendant does believe that it’s an error, that it would
          be an error, to find that any of Defendant’s conduct was
          negligence per se under the record presented to the Court
          and would object to the jury being instructed to that and
          would object to the verdict form that does not have a specific
          question in which the jury would determine whether or not
          Defendant was at fault.
    The court overruled the objections without modifying the instruction.
          Because the jury was instructed the court had already determined
    that CM Holdings was negligent, the special verdict directed the jury to
    decide the remaining issues of causation, comparative fault, and
    damages.    The jury returned a verdict on November 13, finding the
    defendant’s fault caused the plaintiffs’ damages. The jury further found
    Shannon was thirty-five percent at fault and CM Holdings was sixty-five
    percent at fault and awarded the plaintiffs $1,750,000 before the
    reduction for Shannon’s fault.
          On    December      20,    CM Holdings      moved     for   judgment
    notwithstanding the verdict (JNOV) and a new trial, claiming the district
    court erred in finding a violation of the ordinances constituted negligence
    per se. 3 On February 6, 2014, the district court granted the motion for a
    new trial. The district court ruled that the ordinance, as incorporated in
    Iowa’s Uniform Residential Landlord Tenant Act (IURLTA), Iowa Code
    section 562A.15 (2011), did not establish a sufficiently specific standard
    of care to allow plaintiffs to establish negligence per se.
           Plaintiffs appealed, arguing that the district court properly found
    negligence per se applied during trial, and CM Holdings cross-appealed
    on the issues of the grandfather clause and the legal-excuse doctrine.
    The plaintiffs responded to the cross-appeal by arguing CM Holdings
    could not collaterally attack the HAB’s determination that the guardrails
    violated the housing code.      We transferred the case to the court of
    appeals. A divided court of appeals affirmed on both appeals with three
    separate opinions.    The majority held that our decision in Griglione v.
    525 N.W.2d 810
     (Iowa 1994), required a statewide standard for a
    statute or ordinance to establish negligence per se.            The majority
    concluded the district court correctly set aside the verdict because
    “compliance with an ordinance that may or may not be grandfathered
    does   not   constitute   conclusive    proof    of   reasonableness.”    The
    concurrence concluded the IURLTA created a statewide standard that
    satisfied Griglione but that our decision in Montgomery v. Engle, 
    179 N.W.2d 478
    , 484 (Iowa 1970), precluded a negligence per se instruction
    because it held that “evidence of violation of the [housing] ordinance . . .
    is prima facie evidence of negligence.”         The dissent argued the jury
    verdict should be reinstated because the ordinance set a specific
          3CM Holdings also moved for remitter or new trial on grounds the damages
    awarded were excessive but has not pursued that argument on appeal.
    standard of conduct and our cases do not require a statewide standard.
    The remaining issues were not addressed by the court of appeals.
          Both parties applied for further review, which we granted.
          II. Standard of Review.
          “The scope of our review of a district court’s ruling on a motion for
    a new trial depends on the grounds raised in the motion.”            Clinton
    Physical Therapy Servs., P.C. v. John Deere Health Care, Inc., 
    714 N.W.2d 603
    , 609 (Iowa 2006) (quoting Richards v. Anderson Erickson Dairy Co.,
    699 N.W.2d 676
    , 678 (Iowa 2005)).         The question of whether a duty
    exists is a question of law reviewed for correction of errors at law. See id.
    (“[I]f the motion was ‘based on a legal question, our review is on error.’ ”
    (quoting Richards, 699 N.W.2d at 678)); Porter v. Iowa Power & Light Co.,
    217 N.W.2d 221
    , 228 (Iowa 1974) (“The question of existence of duty is a
    matter of law for the court.”). “We are slower to interfere with the grant
    of a new trial than with its denial.” Bryant v. Parr, 
    872 N.W.2d 366
    , 376
    (Iowa 2015) (quoting Cowan v. Flannery, 
    461 N.W.2d 155
    , 157 (Iowa
          “Whether the elements of issue preclusion are satisfied is a
    question of law.” Emp’rs Mut. Cas. Co. v. Van Haaften, 
    815 N.W.2d 17
    22 (Iowa 2012) (quoting Grant v. Iowa Dep’t of Human Servs., 
    722 N.W.2d 169
    , 173 (Iowa 2006)).
          “We review a district court judgment on a ruling for judgment
    notwithstanding the verdict for corrections of errors at law.” Spreitzer v.
    Hawkeye State Bank, 
    779 N.W.2d 726
    , 734 (Iowa 2009). “We examine
    whether substantial evidence supports each element of the claim . . . in a
    light most favorable to the nonmoving party.”            Id.   “Evidence is
    substantial if a jury could reasonably infer a fact from the evidence.” Id.
    (quoting Gibson v. ITT Hartford Ins. Co., 
    621 N.W.2d 388
    , 391 (Iowa
          III. Analysis.
          The central fighting issue on appeal is whether CM Holdings was
    negligent as a matter of law by failing to replace the thirty-two-inch high
    balcony guardrails with forty-two-inch high guardrails. We must resolve
    several related questions. First, CM Holdings argues—and the court of
    appeals ultimately concluded—that under Griglione, only breach of a
    specific statewide statute or rule can constitute negligence per se, while
    the breach of a local ordinance cannot. We disagree and hold that the
    breach of a specific safety-related requirement in a municipal ordinance
    with the force of law may constitute negligence per se.
          Second, CM Holdings argues its property was grandfathered out of
    the forty-two-inch high guardrail requirement. The plaintiffs argue that
    CM Holdings is bound by the HAB’s determination that its thirty-two-
    inch balcony guardrails with the attached lattice violated the code. The
    district court ruled that CM Holdings could not “collaterally attack” the
    HAB determination. We reframe the issue as one of issue preclusion and
    hold that the HAB finding is not preclusive in this tort action.
          Third, CM Holdings contends the HAB’s extension of time to install
    forty-two-inch railings excused its tort liability in the interim. We affirm
    the district court’s ruling rejecting that legal excuse.
          Finally, we conclude neither side was entitled to a directed verdict
    on the grandfather issue under the existing record. That issue must be
    litigated on remand.
          A. Can a Violation of a City Ordinance Constitute Negligence
    Per Se? The court of appeals construed Griglione to hold that only the
    breach of a statewide standard can constitute negligence per se and
    affirmed the order granting a new trial on that basis.       The court of
    appeals understandably relied on this language from Griglione:
          We believe rules of conduct that establish absolute
          standards of care, the violation of which is negligence per se,
          must be ordained by a state legislative body or an
          administrative agency regulating on a statewide basis under
          authority of the legislature. That is the position espoused in
          Restatement (Second) of Torts § 286 (1965) and followed by
          this court in Jorgensen [v. Horton, 
    206 N.W.2d 100
    , 102
          (Iowa 1973)]. We are persuaded that, for purposes of civil
          damages actions based on allegedly negligent actions by
          municipal employees, this principle is sound.
    525 N.W.2d at 812. The plaintiffs argued that language is dicta, but the
    court of appeals concluded that language is controlling. We note that
    language was unnecessary to the decision and is not supported by the
    cited authorities. We resolve the issue by overruling Griglione.
          Our court has long recognized the violation of a municipal safety
    ordinance can be negligence per se. See Hedges v. Conder, 
    166 N.W.2d 844
    , 850–51 (Iowa 1969) (holding party could be negligent per se for
    failing to follow city ordinance requiring use of crosswalks); Kisling v.
    214 Iowa 911
    , 915, 
    243 N.W. 552
    , 554 (1932) (adopting
    general rule that violation of rules of the road in statutes or ordinances
    constitute negligence per se); Tobey v. Burlington, Cedar Rapids & N. Ry.,
    94 Iowa 256
    , 265, 
    62 N.W. 761
    , 764 (1895) (holding violation of speed
    limit ordinance was negligence per se). However, the district court and
    court of appeals questioned the viability of this line of cases based on
    what we recently said in Griglione, a case that did not involve a municipal
    ordinance or code with the force of law.
          The fighting issue in Griglione was whether the violation of a local
    police department’s internal operating procedures constituted negligence
    per se.   Paula Blythe received threatening phone calls from Rodney
    Griglione, her former paramour.     525 N.W.2d at 811.      She called the
    Mt. Pleasant Police Department, and the responding police officer,
    Steven Martin, while interviewing her inside her trailer, heard someone
    yelling profanities outside.   Officer Martin stepped outside in the dark
    and looked around with his flashlight.     Id. He saw Griglione climbing
    over a fence with a large knife in his right hand.      Id.   Griglione ran
    towards Officer Martin, who drew his pistol and fired three times, fatally
    wounding Griglione. Id. at 811–12.
          Griglione’s widow sued Officer Martin, arguing that he was
    negligent per se for violating his department’s operating procedures by
    using deadly force and failing to call for backup or identify himself as a
    police officer before shooting. Id. at 812. The preamble to the operating
    procedures stated,
          The following Police Department Standard Operating
          Procedures are guidelines that are suggested for occurrences
          as specified as follows. They will never replace good, sound
          judgment or common sense, but when confronted with an
          unfamiliar situation should serve as an aid to the Officer.
    Id.   The provisions regarding deadly force included the following
          The Deadly Force Policy is written to guide officers before the
          fact in approaching a potentially critical situation and not
          merely to assist in assessing the possible liability after the
          fact. The use of deadly force in effecting an arrest shall be
          based on the concept of protection of the officer or other
          person from the use, or threat of use of deadly force.
          We concluded that violations of the department’s internal operating
    procedures were not negligence per se for two reasons. Id. First, we held
    that the operating procedures “do not involve the delineation of that type
    of precise standard required to invoke the negligence per se doctrine.”
    Id.   Second, we stated that only the violation of a rule applying
    “statewide” could constitute negligence per se and cited Jorgensen and
    the Restatement (Second) of Torts section 286, in support of that
    proposition. Id. That statement was broader than necessary to decide
    the narrow issue of whether an officer’s violation of his department’s
    internal procedures is negligent per se.    We could have answered “no”
    without addressing local ordinances that have the force of law.
    Moreover, the cited authorities contradict the proposition that only
    violations of statewide standards constitute negligence per se.            In
    Jorgensen, we considered whether the defendant’s failure to follow a
    standard in a private construction safety code was negligence per se.
    206 N.W.2d at 102. We said,
          Statutes and ordinances such as these under discussion are
          a legislative prescription of a suitable precaution, or a fixing
          by law of the standard of care which is required under the
          circumstances, and it must follow that a failure to observe
          the standard of care thus fixed by law is negligence.
    Id. (emphasis added) (quoting Kisling, 214 Iowa at 915, 243 N.W. at 554).
    We ultimately held breach of the private safety code did not establish
    negligence per se, but we noted four times in that opinion that an
    ordinance may serve as the basis for negligence per se. Id. at 102–03.
    Similarly,   the   Restatement   (Second)   of   Torts   expressly   includes
    ordinances as a basis for a standard of care the violation of which is
    negligent per se. Restatement (Second) of Torts § 286, at 25 (Am. Law
    Inst. 1965) (“The court may adopt as the standard of conduct of a
    reasonable man the requirements of a legislative enactment . . . .”); id.
    § 286 cmt. a (“ ‘Legislative enactment’ includes both statutes and
    ordinances.”). The Restatement (Third) of Torts continues to recognize
    that the violation of a local ordinance is negligence per se.            See
    Restatement (Third) of Torts: Liab. for Physical & Emotional Harm § 14
    cmt. a, at 154–55 (Am. Law Inst. 2010) (“This Section most frequently
    applies to statutes adopted by state legislatures, but equally applies to
    regulations adopted by state administrative bodies, ordinances adopted
    by local councils, and federal statutes as well as regulations promulgated
    by federal agencies.”).
           CM Holdings and the court of appeals relied on Montgomery for the
    proposition that the violation of a municipal safety ordinance is merely
    evidence of negligence rather than negligence per se.       179 N.W.2d at
    483–84.    In Montgomery, we did not conclude the violation of an
    ordinance can never be negligence per se; rather we used a fact-specific,
    case-by-case approach for determining “whether the alleged ordinance
    violation constitutes negligence per se or merely prima facie evidence of
    negligence . . . . Each case has been decided in light of the purpose and
    intent of the statute or ordinance involved.” Id. at 483. In Montgomery,
    the plaintiff was injured falling down a stairway that lacked a railing. Id.
    at 480–81. The city municipal code required handrails on stairway exits.
    Id. at 481. We noted “the primary purpose of these statutes appears to
    be protection from fire hazards.”     Id. (quoting Lattner v. Immaculate
    Conception Church, 
    255 Iowa 120
    , 129, 
    121 N.W.2d 639
    , 645 (1963)).
    We said that the violation of a statute is not negligence per se “unless the
    plaintiff [is] a member of the class the statute is designed to protect and
    the harm is one the enactment is designed to protect.”         Id. (quoting
    Lattner, 255 Iowa at 129, 121 N.W.2d at 645).        The plaintiff was not
    fleeing a fire—he was walking down the stairs.             Id. at 478–81.
    Accordingly, we determined that the defendants’ violation of the
    ordinance should have been submitted to the jury with a prima facie
    negligence instruction rather than a negligence per se instruction. Id. at
          We now conclude the scope of the class of people protected by the
    municipal handrail ordinance was viewed too narrowly in Montgomery as
    persons fleeing fires, rather than a broader class of people using such
    stairways routinely to enter or exit the apartment.          To the extent
    Montgomery is inconsistent with our opinion today, we overrule it.
          In Koll v. Manatt’s Transportation Co., a truck driven by Michael
    Manatt and owned by Manatt’s Transportation Company backed over
    David Koll, killing him. 
    253 N.W.2d 265
    , 267 (Iowa 1977). The plaintiff
    alleged the truck lacked equipment required by OSHA and IOSHA
    regulations, specifically a backup alarm audible above the surrounding
    noise level.    Id. at 269.   Koll’s estate sued Manatt’s and argued the
    defendant’s violation of the regulation constituted negligence per se. We
    held that the
          violation by an employer of an OSHA or IOSHA standard is
          negligence per se as to his employee. Such a violation is
          evidence of negligence as to all persons who are likely to be
          exposed to injury as a result of the violation.
    Id. at 270. Accordingly, Koll was unable to establish negligence per se
    against Manatt’s Transportation Company because he was not Manatt’s
    employee. Id.
          In Wiersgalla v. Garrett, we reiterated the governing standard as
          [I]f a statute or regulation . . . provides a rule of conduct
          specifically designed for the safety and protection of a certain
          class of persons, and a person within that class receives
          injuries as a proximate result of a violation of the statute or
          regulation, the injuries “would be actionable, as . . .
          negligence per se.” To be actionable as such, however, “the
          harm for which the action is brought must be of the kind
          which the statute was intended to prevent; and the person
          injured, in order to recover, must be within the class which
          [the statute] was intended to protect.”
    486 N.W.2d 290
    , 292 (Iowa 1992) (citations omitted) (quoting Koll, 253
    N.W.2d at 270).    We hold this standard applies equally to municipal
          The ordinance at issue here requires forty-two-inch high guardrails
    on second-floor or higher balconies. The obvious purpose for requiring a
    forty-two-inch high guardrail on balconies above ground level is to
    protect persons from getting killed or injured falling off the balcony.
    Shannon clearly was within the scope of persons intended to be
    protected from injury by the municipal ordinance. The requirement is
    sufficiently specific to prescribe a standard of care the violation of which
    constitutes negligence per se. See O’Neil v. Windshire Copeland Assocs.,
    197 F. Supp. 2d 507
    , 510 (E.D. Va. 2002) (ruling that apartment
    owner was negligent per se for having balcony guardrail lower than
    required by city building code); Heath v. La Mariana Apartments, 
    180 P.3d 664
    , 669–70 (N.M. 2008) (violation of guardrail spacing requirement
    in ordinance would be negligence per se but for grandfather provision
    excusing landlord from obligation to upgrade railings to current code); cf.
    Brichacek v. Hiskey, 
    401 N.W.2d 44
    , 47 (Iowa 1987) (holding Des Moines,
    Iowa, Municipal Code provision that required a “working lock” lacked the
    requisite specificity for negligence per se); Struve v. Payvandi, 
    740 N.W.2d 436
    , 442–43 (Iowa Ct. App. 2007) (holding statutory requirement
    to maintain heating appliances in a safe and working order was not
    specific enough to support negligence per se theory).
          CM Holdings’ argument that only a violation of a statewide law can
    be negligent per se conflicts with Iowa’s public policy encouraging local
    control over residential housing for public health and safety.          See
    generally Iowa Code § 364.1 (permitting a city to “exercise any power and
    perform any function it deems appropriate to . . . preserve and improve
    the peace, safety, health, welfare, comfort, and convenience of its
    residents”); Star Transp. Co. v. Mason City, 
    195 Iowa 930
    , 953, 
    192 N.W. 873
    , 882 (1923) (“When power to regulate, license, and control is vested
    by the legislature in city councils, there is a broad presumption in favor
    of the validity of the ordinance . . . .”). The legislature has specifically
    allowed      local    housing   ordinances      more    stringent     than    statewide
    standards in the IURLTA. See Iowa Code § 562A.15(1)(a) (requiring the
    landlord to follow greater duties imposed by local building or housing
    codes that materially affect health and safety). 4                     Our legislative
    enactments thus tolerate local variations in housing codes.                   Although
    building codes may differ on either side of a city’s boundary, buildings
    are in fixed locations.         Building owners will not have to deal with
    inconsistent local codes at a single location.
           We see no good reason to limit application of the negligence per se
    doctrine to laws of statewide application. The negligence per se doctrine
    also applies to local ordinances. We next address whether the district
    court correctly instructed the jury that CM Holdings violated the
    ordinance as a matter of a law.
           B. Does the Jury Instruction on Negligence Per Se Require a
    New Trial?           CM Holdings argues it was entitled to a directed verdict
    because the grandfather provision in the ordinance applies as a matter of
    law to permit the thirty-two-inch guardrails, or alternatively, the HAB’s
    extension of time to install forty-two-inch guardrails excused tort
    liability. The district court rejected those arguments, ruling during trial
           4In Crawford v. Yotty, we left open the question whether “the IURLTA imposes
    statutory duties that are applicable to visitors of tenants.” 
    828 N.W.2d 295
    , 304 (Iowa
    2013), overruled on other grounds by Alcala v. Marriott Int’l, Inc., 
    880 N.W.2d 699
    , 708 &
    n.3 (Iowa 2016). We need not answer that question here because the municipal
    ordinance protects visitors as well as tenants using the apartment’s balcony.
    that CM Holdings could not “collaterally attack” the HAB’s determination
    that it violated the guardrail-height ordinance and the extension was not
    a legal excuse for tort liability. The district court instructed the jury that
    the court had already determined CM Holdings had violated the
    ordinance and that violation constituted negligence per se. The district
    court then ordered a new trial based on its posttrial ruling that the
    ordinance did not support a negligence per se theory.           Because we
    reverse that posttrial ruling above, we must decide whether it was
    prejudicial error to give that jury instruction.     We conclude the HAB
    finding of a violation cannot be used by plaintiffs offensively in this tort
    action, and the HAB extension does not excuse tort liability. Whether
    the grandfather provision applies is a mixed question of law and fact to
    be decided on remand.
          1. Is CM Holdings bound by the HAB finding that it violated the
    guardrail ordinance?     “Collateral estoppel” is also known as “issue
    preclusion.”   Winnebago Indus., Inc. v. Haverly, 
    727 N.W.2d 567
    , 571
    (Iowa 2006).   “Issue preclusion prevents parties ‘from relitigating in a
    subsequent action issues raised and resolved in [a] previous action.’ ”
    Emp’rs Mut. Cas. Co., 815 N.W.2d at 22 (quoting Soults Farms, Inc. v.
    797 N.W.2d 92
    , 103 (Iowa 2011)). The doctrine serves several
    purposes: protecting parties from the vexation of relitigating identical
    issues, furthering judicial economy by reducing unnecessary litigation,
    and avoiding the problem of two authoritative but conflicting rulings on
    the same question. Id. We have given preclusive effect to an agency’s
    adjudicatory decisions in subsequent court proceedings under certain
    circumstances.    See, e.g., City of Johnston v. Christenson, 
    718 N.W.2d 290
    , 301–02 (Iowa 2006) (holding board of adjustment decision allowing
    nonconforming use had preclusive effect against city challenging land
    use in subsequent district court litigation); Gardner v. Hartford Ins.
    Accident & Indem. Co., 
    659 N.W.2d 198
    , 206–07 (Iowa 2003) (holding
    industrial commissioner’s approval of contested case settlement barred
    employee’s subsequent bad-faith tort claim against his employer’s
    insurer); Maquoketa Cmty. Sch. Dist. v. George, 
    193 N.W.2d 519
    , 521
    (Iowa 1972) (holding a board decision on appeal from contested case that
    students were not residents of school district had preclusive effect in
    court action against parents to collect tuition). “[A]gency action may be
    adjudicatory if the agency determines an individual’s rights, duties, and
    obligations created by past transactions or occurrences.”       Iowa Elec.
    Light & Power Co. v. Lagle, 
    430 N.W.2d 393
    , 397 (Iowa 1988).
          But we have cautioned against routinely according preclusive effect
    to agency determinations because
          [r]esolution of a[n administrative] dispute does not require
          formal court-like proceedings, and informality is considered
          a virtue of most administrative proceedings. When, however,
          collateral estoppel effect is given issue determinations made
          in an administrative proceeding, informality becomes a
          problem.     Judicial proceedings operate within a system
          where each issue resolved is subject to appellate review.
          Parties develop the crucial issues, introduce the important
          evidence, and have an independent fact finder resolve legal
          and evidentiary conflicts. The reviewability of this process
          ensures clear and careful issue resolution.
                Administrative proceedings are not structured with the
          same goals in mind as those of formal court-like
          proceedings, especially with regard to issue determinations.
    Id. at 398 (quoting Rex R. Pershbacher, Rethinking Collateral Estoppel:
    Limiting the Preclusive Effect of Administrative Determinations in Judicial
    35 Fla. L
    . Rev. 422, 452 (1983)).     Thus, in Chamberlain,
    L.L.C. v. City of Ames, we rejected a property owner’s request to apply
    issue preclusion against a municipality. 
    757 N.W.2d 644
    , 649–50 (Iowa
    2008). The owner planned to build an apartment complex with loft space
    that could be used for sleeping. Id. at 646. Uncertain whether the lofts
    would comply with the ceiling-height requirements of the Ames Housing
    Code, the owner sought and obtained a code interpretation from a city
    official allowing the proposed use. Id. at 646–47. After construction was
    completed, the fire chief determined the ceiling height violated the code,
    a finding upheld by the city’s board of appeals.              Id. at 647.     The city
    issued a certificate of occupancy only after the owner barricaded the
    lofts.    Id.   The owner appealed to the district court, which granted
    summary judgment to the city.              We affirmed because the city code
    allowed the city to override the “initial interpretation” of its employee. Id.
    at 650. Because the initial code interpretation was “not an adjudication
    of rights unalterable by the city,” we held the owner could not use issue
    preclusion against the city.         Id. at 649–50.       Accordingly, we did not
    address the additional requirements for applying the doctrine.
             CM Holdings failed to appeal the finding that its balcony railings
    violated the code and instead sought and obtained an extension of time
    to install new railings. We consider the HAB order an “adjudication of
    rights” for purposes of applying issue preclusion. See id. We next must
    determine whether the plaintiffs, who were not parties to the HAB
    proceeding,     satisfied    the   remaining      requirements      to   apply    issue
    preclusion offensively against CM Holdings. 5
             5The plaintiffs cite no cases applying issue preclusion against a property owner
    in a civil action based on a prior agency determination of a housing code violation. An
    Ohio appellate court rejected the use of issue preclusion based on unappealed building
    code violations.       Credit Reporting Serv., Inc. v. Joseph Sylvester Constr. Co.,
    No. 98 CA 30, 
    1999 WL 669514
    , at *3 (Ohio Ct. App. 1999). There, the contractor failed
    to appeal the building inspector’s notice of violation, and the building appeal board on
    the owner’s appeal found code violations. Id. at *1. The owner sued the contractor for
    the costs to remedy the violations, and the trial court entered summary judgment based
    on the agency finding of code violations. The appellate court reversed, holding that the
    doctrine of issue preclusion did not apply because the code violation was not “actually
    litigated” before the board. Id. at *2. The Ohio appellate court found the contractor’s
           The party invoking issue preclusion must establish four elements:
           (1) the issue in the present case must be identical, (2) the
           issue must have been raised and litigated in the prior action,
           (3) the issue must have been material and relevant to the
           disposition of the prior case, and (4) the determination of the
           issue in the prior action must have been essential to the
           resulting judgment.
    Emp’rs Mut. Cas. Co., 815 N.W.2d at 22 (quoting Soults Farms, Inc., 797
    N.W.2d at 104). “Although offensive use of issue preclusion is allowed in
    Iowa[,] . . . it is more restrictively and cautiously applied than defensive
    issue preclusion.” Gardner, 659 N.W.2d at 203 (quoting Buckingham v.
    Fed. Land Bank Ass’n, 
    398 N.W.2d 873
    , 876 (Iowa 1987)).                            Offensive
    issue preclusion involves two extra considerations:
           (1) whether the opposing party in the earlier action was
           afforded a full and fair opportunity to litigate the issues . . . ,
           and (2) whether any other circumstances are present that
           would justify granting the party resisting issue preclusion
           occasion to relitigate the issues.
    Emp’rs Mut. Cas. Co., 815 N.W.2d at 22 (quoting Soults Farms, Inc., 797
    N.W.2d at 104). One circumstance in which issue preclusion does not
    apply is when “the party sought to be precluded . . . did not have an
    adequate . . . incentive to obtain a full and fair adjudication in the initial
    action.”    Restatement (Second) of Judgments § 28(5)(c) (Am. Law Inst.
    1982); see Hunter v. City of Des Moines Mun. Hous. Auth., 
    742 N.W.2d 578
    , 585 (Iowa 2007) (applying section 28(2) of the Restatement (Second)
    of Judgments); Dettmann v. Kruckenberg, 
    613 N.W.2d 238
    , 246, 249
    (Iowa 2000) (discussing and applying “incentive to litigate” requirement
    to affirm civil judgment giving preclusive effect to criminal conviction
    establishing identity of driver in fatal accident). An adequate incentive
    “ample opportunity to litigate the issues in the notice by appealing to the Board” was
    not sufficient to give the violations preclusive effect in the subsequent civil litigation. Id.
    at *3.
    may be lacking when only a small dollar amount is at stake in the prior
    proceeding. The United States Supreme Court, in the leading case on
    offensive issue preclusion, cautioned that the doctrine should not be
    applied against a defendant who “in the first action is sued for small or
    nominal damages [and thus] may have little incentive to defend
    vigorously.” Parklane Hosiery Co. v. Shore, 
    439 U.S. 322
    , 330, 
    99 S. Ct. 645
    , 651, 
    58 L. Ed. 2d 552
    , 561 (1979).                In Dettmann, we quoted a
    leading commentator’s observation “that preclusive effect is given to a
    judgment only if the party precluded had the opportunity and incentive
    to litigate the matter fully.” 613 N.W.2d at 246 (quoting Allan D. Vestal,
    Issue Preclusion and Criminal Prosecutions, 
    65 Iowa L
    . Rev. 281, 340
    (1980)).   Thus, courts will decline to apply issue preclusion when the
    party to be precluded lacked an incentive to litigate in the prior
    proceeding. See, e.g., Bd. of Educ. v. Gray, 
    806 S.W.2d 400
    , 403 (Ky. Ct.
    App. 1991) (declining to give unemployment compensation decision
    preclusive effect in employee’s breach of contract action because of the
    “minimal” amount at stake in the agency proceeding); 6 Hadley v.
             6Other courts have upheld the offensive use of issue preclusion against a party
    that litigated and lost an issue in an administrative proceeding, when the amount at
    stake provided the incentive to litigate in the administrative forum. For example, in
    Bellermann v. Fitchburg Gas & Electric Light Co., the Supreme Judicial Court of
    Massachusetts affirmed a trial court ruling applying issue preclusion against an electric
    utility in a civil action by its customers for damages resulting from a storm-related
    power outage. 
    18 N.E.3d 1050
    , 1069 (Mass. 2014). The Department of Public Utilities
    (DPU) had conducted a five-day adjudicatory hearing in which the utility was
    represented by counsel. Id. The DPU issued a 215-page decision with numerous
    findings on inadequacies in the utility’s storm preparedness and imposed a $4.6 million
    fine while denying recovery of nearly $7 million in storm-related costs. Id. at 1066. The
    Bellermann court rejected the utility’s argument that it lacked “an adequate incentive to
    dispute its purported failures before the DPU.” Id. at 1067.
           Similarly, in United States v. Karlen, the United States Court of Appeals for the
    Eighth Circuit found an adequate incentive to litigate at the agency. 
    645 F.2d 635
    639–40 (8th Cir. 1981) (affirming district court ruling giving preclusive effect to an
    agency decision). Merrill Karlen leased tribal land to graze cattle. Id. at 637. The
    Bureau of Indian Affairs (BIA) canceled his lease for excessive hay cutting and assessed
    27 P.3d 600
    , 603–04 (Wash. 2001) (en banc) (concluding $95
    fine for traffic violation provided insufficient incentive to appeal finding of
    guilt or to justify use of issue preclusion in subsequent personal injury
    lawsuit). 7 As the Washington Supreme Court recognized, “There must be
    sufficient motivation for a full and vigorous litigation of the issue” in the
    prior proceeding. Hadley, 27 P.3d at 604; see also 18 Charles A. Wright,
    et al., Federal Practice and Procedure § 4423, at 612 (2d ed. 2002) (“The
    most general independent concern reflected in the limitation of issue
    preclusion by the full and fair opportunity requirement goes to the
    incentive to litigate vigorously in the first action.”).
           A settlement may provide another explanation for a lack of
    incentive to litigate in the prior proceeding.                See, e.g., Arizona v.
    530 U.S. 392
    , 414, 
    120 S. Ct. 2304
    , 2319, 
    147 L. Ed. 2d 374
    395 (2000) (declining to give preclusive effect to prior consent decree,
    noting “settlements ordinarily occasion no issue preclusion”); Adam v.
    380 N.W.2d 716
    , 721 (Iowa 1986) (declining to give preclusive
    damages of $57,325. Id. Karlen requested a formal hearing. An administrative law
    judge (ALJ) conducted a two-day de novo hearing in which Karlen was represented by
    counsel. Id. at 637, 640. The ALJ issued a written ruling affirming cancellation of the
    lease but setting aside the damage award for lack of jurisdiction. Id. at 637. The ALJ’s
    decision was affirmed by the Interior Board of Indian Appeals. Id. Karlen did not seek
    judicial review. Id. The tribe’s trustee later sued Karlen for money damages, and the
    district court granted partial summary judgment against Karlen applying offensive issue
    preclusion based on the ALJ’s decision terminating the lease for excessive haying. Id.
    at 638. The Eighth Circuit affirmed, noting Karlen’s incentive to litigate the $57,325
    damage assessment. Id. at 640.
           7The Iowa Motor Vehicle Code provides that “No record of the conviction of a
    person for any violation of this chapter or other traffic regulations less than a felony
    shall be admissible as evidence in any court in any civil action.” Iowa Code § 321.489
    (2011). We have applied that statute to hold convictions for traffic violations resulting
    from a contested trial are not given res judicata effect in a subsequent civil action.
    Berding v. Thada, 
    243 N.W.2d 857
    , 859–60 (Iowa 1976). Guilty pleas, however, may
    come into evidence as admissions. Id. at 860. Guilty pleas and Alford pleas in which a
    court found a factual basis for the plea may also be given preclusive effect in
    subsequent civil actions. Emp’rs Mut. Cas. Co., 815 N.W.2d at 23–24.
    effect to a prior district court ruling on a statutory exemption when the
    losing party settled on appeal).
            A key purpose of issue preclusion is to avoid the cost of
    unnecessary litigation.   Emp’rs Mut. Cas. Co., 815 N.W.2d at 22.              We
    would    undermine    that   purpose    if   we   gave   preclusive   effect   to
    administrative decisions informally resolving alleged violations because
    raising the stakes preclusively would motivate parties to litigate instead
    of settling the agency matter. See Salida Sch. Dist. R-32-J v. Morrison,
    732 P.2d 1160
    , 1165 (Colo. 1987) (en banc) (declining to give preclusive
    effect to unemployment compensation decision in wrongful-termination
    lawsuit because to do so would result in more contested, lengthy
    hearings causing “judicial economy [to] be frustrated, rather than
    improved”).     We do not want to discourage informal, voluntary
    resolutions. See Peak v. Adam, 
    799 N.W.2d 535
    , 543 (Iowa 2011) (“The
    law favors settlement of controversies.” (quoting Waechter v. Aluminum
    Co. of Am., 
    454 N.W.2d 565
    , 568 (Iowa 1990))).
            In our view, CM Holdings lacked an adequate incentive to litigate
    the grandfather issue before the HAB. At that time, it only faced a $1090
    fine (not a wrongful-death lawsuit) and essentially attained a compromise
    settlement through the order that suspended that fine and granted its
    requested extension to install the new railings.          CM Holdings’ new
    owners had recently acquired multiple distressed properties and had
    been working proactively with the city to correct numerous violations at
    the apartment complexes. CM Holdings had already ordered new forty-
    two-inch balcony guardrails for installation. It had every reason to pick
    its battles with the housing officials and little or no reason to challenge
    the finding of a violation in the very order that granted its requested
    extension to install the new guardrails and suspended the fine. The cost
    of an administrative appeal to litigate the grandfather issue presumably
    would have greatly exceeded the $1090 fine.
          We conclude the doctrine of offensive issue preclusion should not
    apply here because CM Holdings, having obtained its requested
    extension and suspension of the fine, lacked an adequate incentive to
    appeal the violation.     Accordingly, we hold the district court erred by
    ruling that CM Holdings was bound by the HAB’s finding of a violation.
    Because we resolve the question on this ground, we do not reach the
    remaining requirements for offensive use of issue preclusion.
          Alternatively, the plaintiffs argue CM Holdings is bound by
    statements it made at the HAB meeting purportedly admitting the railing
    violated the ordinance:
          If a party testifies deliberately to a concrete fact, not as a
          matter of opinion, estimate, appearance, inference, or
          uncertain memory, but as a considered circumstance of the
          case, his [or her] adversary is entitled to hold him [or her] to
          it as an informal judicial admission.
    Yockey v. State, 
    540 N.W.2d 418
    , 421 (Iowa 1995) (quoting Snittjer Grain
    Co. v. Koch, 
    246 Iowa 1118
    , 1127, 
    71 N.W.2d 29
    , 34 (1955)).              Estes’
    statements were not made under oath and were insufficiently concrete to
    establish a judicial admission.     Estes and Laswell did not specifically
    admit the guardrails violated the municipal code. See id. at 421 (holding
    that a plaintiff who “expressly conceded during her testimony” that she
    was not fired in retaliation “had the effect of an informal judicial
    admission”). Although Estes said at the HAB meeting the guardrails with
    the attached lattice “were just not the right height,” he also noted that
    the “code ha[d] changed.”     He stopped short of saying the grandfather
    provision did not apply. Accordingly, the statements at the HAB meeting
    fall short of a judicial admission in this tort action. Nor do we equate the
    equivocal statements to a guilty plea or Alford plea for purposes of issue
    preclusion under Employers Mutual Casualty Co., as the plaintiffs
    contend. Such pleas require a judicial finding of a factual basis. Emp’rs
    Mut. Cas. Co., 815 N.W.2d at 24. That requirement is not met here.
          2. Was CM Holdings legally excused based on the HAB’s extension?
    CM Holdings moved for a directed verdict and JNOV on grounds the
    HAB’s extension of time to allow installation of forty-two-inch guardrails
    excused tort liability.       The district court correctly concluded the
    extension merely suspended enforcement of the administrative penalty
    and did not excuse tort liability.
          “The   legal   excuse    doctrine    allows   a   person   to   avoid   the
    consequences of a particular act or type of conduct by showing
    justification for acts that otherwise would be considered negligent.”
    Rowling v. Sims, 
    732 N.W.2d 882
    , 885 (Iowa 2007). We have identified
    four categories of legal excuse:
                (1) anything that would make it impossible to comply
          with the statute or ordinance;
                (2) anything over which the [person] has no control
          which places [him or her] in a position contrary to the
          provisions of the statute or ordinance;
                (3) where the [person] is confronted by an emergency
          not of [his or her] own making, and by reason of such an
          emergency, [he or she] fails to obey the statute; and
                (4) where a statute specifically provides an excuse or
    Hagenow v. Schmidt, 
    842 N.W.2d 661
    , 673 (Iowa 2014), overruled on
    other grounds by Alcala, 880 N.W.2d at 708 & n.3. A jury may only be
    instructed on the category of legal excuse that is supported by the
    evidence. See id.
          CM Holdings relies on section 60-101(3): “The housing appeals
    board shall . . . [r]ule on requests for additional time, provided that the
    granting of such additional time does not endanger the life, health or
    safety of the occupants or the integrity of the structure.” Des Moines,
    Iowa, Municipal Code § 60-101(3).                 An extension for time under this
    section does not specifically excuse the violation. A request for time is
    made when the HAB has determined there has been a violation of the
    housing code. See id. § 60-85(a)(2). The notice granting an extension of
    time explicitly states the Grand Stratford Apartments are in violation of
    the housing code. The suspension of a fine and extra time to complete
    repairs does not mean the property complies with the code during the
    time allowed. To the contrary, the notice states, “The property was not
    brought into compliance” with the code.
          CM Holdings cites no case holding that an agency’s extension of
    time to remedy code violations provides the property owner a legal excuse
    in a third party’s tort action arising from the violation. We affirm the
    district court’s ruling rejecting CM Holdings’ legal excuse.
          3. Did the district court correctly rule the grandfather provision did
    not apply as a matter of law?               CM Holdings argues the forty-two-inch
    guardrail requirement in the current municipal code did not apply to the
    Grand Stratford Apartments based on the grandfather provision in the
    housing code. The district court rejected that argument by erroneously
    applying collateral estoppel based on the HAB finding 8 and did not
    address this issue in its posttrial ruling granting a new trial. 9
          8The   district court order stated,
          The Court also finds that since the Defendant did not file an appeal with
          the HAB, the Notice of Inspection finding that the lattice did create a
          change that required the guardrail to [be] updated to be in compliance
          with the new code height of 42 inches, cannot now be collaterally
          attacked by the Defendant in this lawsuit. As noted above, Defendant
          never followed the appeal process, never filed an appeal from the city’s
           The purpose of a grandfather provision for property owners is to
    “avoid the harsh effect of the retroactive application” of a new rule of law.
    See State v. Finders, 
    743 N.W.2d 546
    , 549 (Iowa 2008) (discussing the
    grandfather provision in the sex offender residency restriction law).
    Housing codes include grandfather provisions to avoid constitutional
    challenges. As the Maine Supreme Court recently observed,
           A grandfather clause, which allows the limited continuance
           of nonconformities, is included in zoning ordinances in order
           to avoid takings challenges. It is designed to strike a balance
           between     a    municipality’s     interest   in    abolishing
           nonconformities and the interests of property owners in
           maintaining land uses that were allowed when they
           purchased their property.
    Day v. Town of Phippsburg, 
    110 A.3d 645
    , 649 (Me. 2015) (citation
           The grandfather provision in the Des Moines housing code states:
           The provisions of this article shall apply to the maintenance,
           repair, equipment, use and occupancy of all residential
           rental buildings and accessory structures now in existence
           or hereafter constructed, rehabilitated, renovated or
           converted to residential use within the corporate limits . . . .
           Any structure that was in compliance on the day previous to
           the adoption of this code will be allowed to remain.
    Des Moines, Iowa, Municipal Code § 60-5 (emphasis added).
           CM Holdings relies on trial testimony the thirty-two-inch balcony
    railings were code-compliant the day before the current ordinance was
    enacted in 2005 and therefore should be grandfathered. The plaintiffs
           determination, and never challenged that it was obligated to install 42
           inch guardrails on the balconies.
           9CM   Holdings argued in its motion for judgment notwithstanding the verdict
    that the guardrails were grandfathered in. The district court’s ruling on CM Holdings’
    posttrial motions granted CM Holdings a new trial for instructing the jury that the
    violation of a city ordinance could be negligence per se and stated “it is unnecessary to
    address any other issues raised in Defendant’s post-trial motions.”
    rely on trial testimony by the housing inspector and his supervisor that
    latticework installed on the balcony railings after 2005 created a false
    sense of security and triggered an obligation to upgrade the balcony
    guardrails to the current forty-two-inch height requirement. The district
    court never decided that specific issue, nor was it submitted to the jury.
    Under the existing trial record, neither side was entitled to a directed
    verdict.       Although the district court correctly denied CM Holdings’
    motions for a directed verdict and JNOV on the grandfather provision
    under this record, it erred by granting the plaintiffs’ motion for partial
    directed verdict and by instructing the jury, over defendant’s objection,
    that the thirty-two-inch high balconies constituted negligence per se.10
    That instructional error requires a new trial on liability and damages.
           10The  plaintiffs contend CM Holdings waived error on the grandfather defense by
    failing to specifically object to the lack of a jury instruction on that issue or reoffer its
    own jury instruction at the instruction conference. We disagree.               CM Holdings
    preserved error by objecting to the verdict form and Instruction No. 15 that instructed
    the jury the court had already determined the failure “to install guardrails that were at
    least 42 inches in height on the balcony” was a violation of law and was negligent.
    CM Holdings’ objection to that instruction and verdict form invited the court to
    reconsider its legal ruling and reiterated its disagreement with that ruling. That ruling
    rejected the grandfather argument that had been briefed and argued in the motions for
    summary judgment and motion for directed verdict, issues that were quite familiar to
    the trial judge. Counsel for CM Holdings clearly articulated the perceived error in the
    jury instructions:
                   Defendant does believe that it’s an error, that it would be an
           error, to find that any of Defendant’s conduct was negligence per se
           under the record presented to the Court and would object to the jury
           being instructed to that and would object to the verdict form that does
           not have a specific question in which the jury would determine whether
           or not Defendant was at fault.
    Accordingly, CM Holdings’ objection was sufficiently specific to alert the district court to
    the legal error in its instruction and verdict form. See Iowa R. Civ. P. 1.924; Moser v.
    387 N.W.2d 599
    , 604 (Iowa 1986) (“The objection must be sufficiently specific
    to alert the trial court to the basis of the complaint so that if error does exist the court
    may correct it before placing the case in the hands of the jury.”). We have never
    required a party to offer its own jury instruction in addition to objecting to the court’s
    instruction in order to preserve error.
    See Bryant, 872 N.W.2d at 380 (“The general rule is that when a new
    trial is granted, all issues must be retried.” (quoting McElroy v. State, 
    703 N.W.2d 385
    , 389 (Iowa 2005))); Heath, 180 P.3d at 670 (holding
    negligence per se theory is inapplicable when balcony railings may be
    grandfathered out of current building code). On remand, the parties may
    litigate the grandfather issue.
          IV. Conclusion.
          For those reasons, we vacate the decision of the court of appeals
    and reverse the district court’s posttrial rulings on the doctrine of
    negligence per se. We affirm the district court’s ruling rejecting the legal-
    excuse doctrine. We remand this case for a new trial consistent with this
    opinion.     Costs shall be assessed equally to the plaintiffs and the