Gershon v. Back ( 2023 )


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    ELANA GERSHON v. RONALD BACK
    (SC 20599)
    McDonald, D’Auria, Mullins, Ecker and Alexander, Js.
    Syllabus
    The plaintiff, whose marriage to the defendant previously had been dissolved
    by a New York court, appealed to the Appellate Court from the judgment
    of the trial court, which dismissed her motion to open and set aside
    the final New York judgment of divorce for lack of subject matter
    jurisdiction. Before their marriage, the parties entered into a prenuptial
    agreement, pursuant to which the plaintiff waived her interest in certain
    of the defendant’s business interests. During the divorce proceedings,
    the plaintiff challenged the enforceability of the prenuptial agreement,
    but the New York court rejected the claim, finding no evidence of fraud
    or overreaching by the defendant. The parties eventually settled their
    dispute by way of a separation agreement, which superseded the prenup-
    tial agreement and resolved the parties’ respective financial and property
    rights. The separation agreement also included a choice of law provision,
    which designated New York law as governing the agreement, and a
    provision incorporating New York’s plenary action rule, which requires
    a party seeking to modify or vacate a separation agreement that survives
    a final judgment of divorce to file a plenary action on the contract
    instead of a motion to open, modify or vacate the divorce judgment.
    The final judgment of divorce incorporated the separation agreement
    by reference but provided that the separation agreement would survive
    and not be merged into the judgment. The parties both later moved
    to Connecticut, where the plaintiff registered the New York divorce
    judgment pursuant to statute (§ 46b-71 (a)). Thereafter, the plaintiff
    moved to open and set aside the divorce judgment in the Superior
    Court, claiming that it was obtained through the defendant’s fraudulent
    conduct. The plaintiff requested that the Connecticut court open the
    New York divorce judgment and vacate the settlement agreement.
    Applying New York law, the trial court concluded that, because the
    separation agreement was incorporated but not merged into the divorce
    judgment, the plaintiff could not challenge the enforceability of the
    agreement by way of a motion but, rather, was required to do so by
    commencing a plenary action. The trial court then dismissed the plain-
    tiff’s motion for lack of subject matter jurisdiction and rendered judg-
    ment for the defendant. The Appellate Court agreed with the trial court
    that New York’s plenary action rule was substantive for choice of law
    purposes but disagreed with the trial court’s conclusion that the trial
    court lacked subject matter jurisdiction, relying on, among other things,
    the jurisdiction conferred by § 46b-71 (b). Accordingly, the Appellate
    Court concluded that the trial court should have denied, rather than
    dismissed, the plaintiff’s motion to open and set aside the divorce judg-
    ment. On the granting of certification, the plaintiff appealed to this court
    from the Appellate Court’s judgment.
    Held that the Appellate Court correctly concluded that the New York plenary
    action rule is substantive, and not procedural, for choice of law purposes
    and that the trial court should have denied, rather than dismissed, the
    plaintiff’s motion to open and set aside the divorce judgment:
    Under the conflict of law rules governing foreign matrimonial judgments
    registered in Connecticut, as codified in § 46b-71 (b), the plaintiff’s
    motion to open and set aside the divorce judgment was governed by
    New York substantive law and Connecticut procedural law, and that
    approach was consistent with the well established principle that, in a
    choice of law situation, the forum state will apply its own rules to
    issues of procedure and matters of judicial administration, even if the
    substantive law of another jurisdiction applies, because it would often
    be disruptive or difficult to apply the local rules of another state.
    Although New York’s plenary action rule, which is principally concerned
    with preserving the parties’ vested contractual rights to enforce the
    separation agreement in a separate civil action, fell into a gray area
    between issues relating primarily to judicial administration and those
    concerned primarily with the rights and liabilities of the parties, this
    court concluded that the plenary action rule was so interwoven with
    the plaintiff’s cause of action as to be deemed substantive for choice of
    law purposes.
    The fact that the parties explicitly incorporated the New York plenary
    action rule into the separation agreement, which provided that their
    contractual rights could not be invalidated or otherwise affected by any
    final judgment of divorce, was a weighty reason for applying that law
    rather than the local law of the forum, insofar as it demonstrated that
    the issue was one to which the parties had likely given thought.
    Moreover, the application of the New York plenary action rule would
    affect the ultimate substantive outcome of the case because the parties
    had contractual rights that could not be undone by modifying the divorce
    judgment, there was, to this court’s knowledge, no settled precedent
    classifying the plenary action rule as procedural or substantive for choice
    of law purposes, and the application of that rule would not impose
    an undue burden on Connecticut courts, which have recognized that
    separation agreements are contracts that may be litigated independently
    of a divorce judgment in a civil action sounding in contract.
    Argued October 13, 2022—officially released February 21, 2023
    Procedural History
    Motion by the plaintiff to open a foreign judgment
    of dissolution, brought to the Superior Court in the
    judicial district of Stamford-Norwalk, where the court,
    Hon. Michael E. Shay, judge trial referee, dismissed
    the plaintiff’s motion, and the plaintiff appealed to the
    Appellate Court, Lavine, Bright and Beach, Js., which
    reversed the judgment of the trial court and remanded
    the case with direction to deny the motion, from which
    the plaintiff, on the granting of certification, appealed
    to this court. Affirmed.
    James P. Sexton, with whom were Julia K. Conlin
    and, on the brief, John R. Weikart, for the appellant
    (plaintiff).
    Kenneth J. Bartschi, with whom were Karen L. Dowd
    and, on the brief, Wesley W. Horton and Joseph T.
    O’Connor, for the appellees (defendants).
    Opinion
    ECKER, J. New York’s so-called ‘‘plenary action rule’’
    requires a party seeking to modify or vacate a separation
    agreement that survives a final judgment of divorce to
    file a plenary action on the contract instead of a motion
    to open, modify or vacate the divorce judgment. This
    certified appeal requires us to determine whether New
    York’s plenary action rule is procedural or substantive
    for choice of law purposes. The trial court concluded
    that the rule was substantive and dismissed for lack
    of subject matter jurisdiction the motion, filed by the
    plaintiff, Elana Gerson, to open and set aside the final
    judgment of divorce. The Appellate Court agreed that
    the New York rule was substantive but disagreed that
    the trial court lacked subject matter jurisdiction and,
    therefore, concluded that the plaintiff’s motion should
    have been denied instead of dismissed. Gershon v. Back,
    
    201 Conn. App. 225
    , 253–54, 
    242 A.3d 481
     (2020). We
    affirm the judgment of the Appellate Court.
    This case has a long and contentious history. The
    plaintiff and the defendant, Ronald Back,1 were married
    on August 16, 1997. Prior to their marriage, the parties
    entered into a prenuptial agreement, pursuant to which
    the plaintiff waived her interest in the defendant’s sepa-
    rate property, including his business interest in Fla-
    vormatic Industries (Flavormatic). During their mar-
    riage, the parties resided in New York and had two
    children. In February, 2009, the parties separated, and
    the plaintiff commenced a divorce action in the New
    York Supreme Court (New York court). The plaintiff
    challenged the enforceability of the prenuptial agree-
    ment, but the New York court rejected the plaintiff’s
    claim, finding that she ‘‘had presented no evidence
    establishing that the prenuptial agreement was pro-
    cured by the defendant’s fraud or overreaching.’’ (Empha-
    sis omitted; internal quotation marks omitted.)
    In April, 2011, during their divorce trial, the parties
    settled their dispute by entering into a ‘‘[s]tipulation of
    [s]ettlement and [a]greement’’ (separation agreement),
    which superseded the prenuptial agreement and resolved
    the parties’ ‘‘respective financial and property rights,
    support, and all other respective rights, remedies, privi-
    leges and obligations to each other, arising out of the
    marriage . . . .’’ Pursuant to the separation agreement,
    the parties agreed to keep their own separate property
    and the income and appreciation thereof ‘‘free from any
    claim whatsoever from the other party.’’ Additionally,
    the parties agreed to waive their respective rights to
    each other’s retirement accounts and to divide the pro-
    ceeds of the sale of the marital residence. The defendant
    also agreed to pay the plaintiff $400,000 ‘‘[a]s further
    equitable distribution of the parties’ assets . . . .’’ The
    separation agreement contains a choice of law provi-
    sion, which provides that ‘‘[a]ll matters affecting the
    execution, interpretation, performance and enforce-
    ment of this [a]greement and the rights of the parties
    hereto shall be governed by the laws of the [s]tate of
    New York.’’
    The separation agreement incorporates New York’s
    plenary action rule by explicitly providing that it ‘‘shall
    not be invalidated or otherwise affected by any decree
    or judgment of separation or divorce made by any court
    in any action [that] may presently exist or may hereafter
    be instituted by either party against the other for a separa-
    tion or divorce, and the obligations and covenants of
    this [a]greement shall survive any decree or judgment
    of separation or divorce and shall not merge therein,
    and this [a]greement may be enforced independently
    of such decree or judgment.’’ The separation agreement
    also states that ‘‘[b]oth parties agree, stipulate and con-
    sent that no judgment, order or decree in any action
    for divorce or separation, whether brought in the [s]tate
    of New York, or in any other state or country having
    jurisdiction [over] the parties hereto, shall make any
    provisions for alimony or child support or affect the
    property rights of either party in a manner inconsistent
    with the provisions of this [a]greement, but if any provi-
    sion is made in any judgment, order or decree which
    is inconsistent with the provisions of this [a]greement,
    or imposes a different or greater obligation on either
    of the parties hereto than provided in this [a]greement,
    the provisions of this [a]greement shall take precedence
    and shall be the primary obligation of both of the parties
    hereto. It is further agreed that upon the trial of any
    action [that] may hereafter be instituted by either of
    the parties against the other for an absolute divorce in
    any court of competent jurisdiction, the party instituting
    such action shall read the provisions of this [a]greement
    relating to maintenance and support into the record of
    such action as a stipulation between the parties as to
    the questions of maintenance and support. Such party
    shall further request that the decree shall contain a
    provision specifically reciting, in words or substance,
    ‘said [a]greement is not merged in, but survives this
    decree, and the parties thereof are hereby ordered to
    comply with it on its terms at all times and places.’ ’’
    On May 11, 2011, the New York court dissolved the
    parties’ marriage in a final judgment of divorce, which
    incorporated the separation agreement by reference but
    provided that the separation agreement ‘‘shall survive
    and shall not be merged in this judgment . . . .’’ The
    judgment of divorce further stated that ‘‘jurisdiction
    over all matters affecting the execution, interpretation,
    performance and enforcement of this judgment [and/or]
    the [separation agreement] . . . shall be as specifically
    provided by the parties’ [separation agreement].’’
    The plaintiff remarried three days later and moved
    to Greenwich with her new husband and the parties’
    children. The defendant later remarried and moved to
    Connecticut, as well. On October 27, 2014, the plaintiff
    registered the final judgment of divorce in the Superior
    Court in the judicial district of Stamford-Norwalk pursu-
    ant to General Statutes § 46b-71.2
    Extensive litigation in the Superior Court followed.
    In November, 2014, the plaintiff moved to modify the
    judgment to increase the defendant’s child support obli-
    gations, arguing that ‘‘there has been a substantial
    change in circumstances since the date of judgment in
    that three years have passed since the order was entered
    . . . and the defendant’s income has increased by at
    least [15] percent . . . .’’3 In connection with this
    motion, the plaintiff obtained discovery regarding the
    defendant’s finances for the three years preceding the
    filing of the motion. Following full disclosure of the
    parties’ respective finances, the trial court granted the
    plaintiff’s motion, increased the defendant’s child sup-
    port obligation, and awarded the plaintiff attorney’s
    fees.
    After the trial court’s order issued, there was a flurry
    of further litigation, including motions for reargument
    filed by both parties, the defendant’s motion to offset
    his child support obligation with a credit for college
    room and board expenses, and the plaintiff’s motions
    for contempt due to the defendant’s failure to pay the
    retroactive amount of his increased child support obli-
    gation and the plaintiff’s attorney’s fees. The trial court
    denied the motions for reargument, granted the defen-
    dant’s motion for a credit, and denied the plaintiff’s
    motions for contempt.
    The plaintiff then filed a motion to open and set aside
    the divorce judgment, which is the operative motion at
    issue in this appeal. In her motion, the plaintiff claimed
    that she had learned during the modification proceeding
    that the divorce judgment ‘‘was obtained through the
    fraudulent conduct of the defendant’’ in that he ‘‘made
    material misrepresentations of fact to the court and to
    the plaintiff in his sworn financial statement provided
    at the time of the settlement.’’ Specifically, referring to
    the defendant’s ‘‘[a]ttached 2010 [i]ncome [i]nforma-
    tion,’’ the plaintiff alleged that the defendant’s sworn
    statement of net worth dated April 1, 2011, listed his
    gross income for the year 2011 as ‘‘0.00,’’ even though
    his W-2 form reported wages from Flavormatic in the
    amount of $1,900,000 in 2011.4 (Emphasis omitted; inter-
    nal quotation marks omitted.) The plaintiff further alleged
    that the defendant ‘‘stockpiled money in his corporation
    in order to avoid equitable distribution of marital assets
    and to avoid paying alimony and child support.’’ (Empha-
    sis omitted.) According to the plaintiff, ‘‘there is a rea-
    sonable probability that the result of the settlement
    would have been different had the defendant not made
    material misrepresentations of fact . . . .’’ The plain-
    tiff’s motion asked the court to open the final judgment
    of divorce, to vacate the settlement agreement, to order
    a new trial, and to award the plaintiff attorney’s fees.
    In an accompanying memorandum of law, the plaintiff
    requested postjudgment discovery, arguing that she had
    met her burden under Oneglia v. Oneglia, 
    14 Conn. App. 267
    , 
    540 A.2d 713
     (1988), of demonstrating sufficient
    indicia of fraud to justify opening the judgment and
    conducting further discovery. See 
    id., 270
     (plaintiff was
    permitted to conduct postjudgment discovery if she
    ‘‘was able to substantiate her allegations of fraud beyond
    mere suspicion’’).
    The defendant opposed the plaintiff’s motion to open,
    arguing that the plaintiff had failed to state a claim for
    fraud or misrepresentation under New York law because
    the defendant’s 2011 statement of net worth was not
    inaccurate. The defendant explained that his ‘‘income
    for 2011 could not be listed in March of 2011, [because]
    over 75 percent of the year remained,’’ and, instead,
    ‘‘[a]s properly and plainly stated in the statement of net
    worth, [the defendant] listed his total income for 2010
    [because] that was the last full year of income avail
    able.’’ (Emphasis omitted.) The defendant further claimed
    that (1) the plaintiff was collaterally estopped from
    litigating the issue of the defendant’s net worth because
    she ‘‘was provided with substantial discovery regarding
    [the defendant’s] businesses during the divorce action’’
    and previously had claimed in that action, prior to its
    settlement, that the defendant was stockpiling income
    in Flavormatic, (2) the plaintiff ratified the separation
    agreement by accepting the benefits of the agreement
    for more than seven years, and (3) the plaintiff’s motion
    was untimely under the New York statute of limitations
    governing claims of fraud.
    The trial court conducted a three day evidentiary
    hearing pursuant to Oneglia to determine whether the
    plaintiff could substantiate her allegations of fraud to
    a sufficient degree to allow postjudgment discovery. At
    the hearing, the trial court heard testimony from the
    defendant, the plaintiff, and the plaintiff’s expert wit-
    ness in forensic accounting, who testified regarding the
    defendant’s income and retained earnings in Flavormatic
    for the year 2011.
    Following the hearing, the trial court issued a memo-
    randum of decision, denying the plaintiff’s request for
    postjudgment discovery. The trial court concluded that
    the choice of law provision in the separation agreement
    ‘‘was arrived at without any fraud or duress, and with
    the advice of counsel, [that] it should be given effect,’’
    and, therefore, that New York law ‘‘relating to postjudg-
    ment discovery in matrimonial cases . . . should ulti-
    mately control and not Oneglia . . . .’’ The court
    observed that, in New York, postjudgment discovery is
    not permitted unless there is ‘‘an affirmative, factual
    showing, at least prima facie, that the agreement was
    unfair or unreasonable when executed or unconsciona-
    ble at the time of the [rendering] of final judgment.’’
    (Emphasis omitted; internal quotation marks omitted.)
    Applying this standard, the court concluded that the
    plaintiff had ‘‘failed to meet her burden, with at least
    a prima facie showing, either that the [separation agree-
    ment] was unfair or unreasonable when negotiated, or
    unconscionable when the [divorce] judgment was [ren-
    dered], or that the defendant’s actions amounted to
    wilful fraud or fraudulent concealment. Moreover, she
    has not established that, even if the judgment were to
    be opened and the [separation agreement] were to be
    set aside . . . that the resulting judgment would likely
    be substantially different,’’ reasoning that (1) the New
    York court had sustained the validity of the parties’
    prenuptial agreement, finding no evidence of fraud or
    overreaching, (2) under the prenuptial agreement, the
    ‘‘ ‘operative event’ ’’ for purposes of the division of mari-
    tal property was the filing of the complaint for divorce
    in February, 2009, and, therefore, ‘‘the relevant income
    [was] not the defendant’s income for 2011 but, rather,
    that of the years 2004 through 2008,’’ (3) the large
    increase in the defendant’s income following the render-
    ing of the final judgment of divorce in 2011 was not the
    product of ‘‘fraud or fraudulent intent on the part of
    the defendant’’ but plausible business decisions, and
    (4) ‘‘the plaintiff has accepted the benefit of the agree-
    ment for more than three years and, by so doing, ‘effec-
    tively ratified’ it, and she should be estopped from chal-
    lenging it on the basis of fraud.’’
    Having determined that the plaintiff was not entitled
    to postjudgment discovery, the trial court addressed
    New York law regarding the finality of judgments ‘‘in
    family relations matters, [when] the judgment is based
    [on] an agreement of the parties.’’ The trial court consid-
    ered it critically important that the separation agree-
    ment was incorporated but not merged into the final
    judgment of divorce, pointing out that, in New York,
    ‘‘[i]t is well settled that a party to a stipulation that is
    incorporated but not merged into a judgment of divorce
    cannot challenge the enforceability of the stipulation
    by way of a motion but, rather, must do so by com-
    mencement of a plenary action.’’ The trial court ordered
    the parties to show cause why the plaintiff’s motion to
    open and set aside the judgment ‘‘should not be denied
    consistent with New York law.’’
    The trial court entertained oral argument on its order
    to show cause, after which it dismissed the plaintiff’s
    motion for lack of subject matter jurisdiction. The court
    explained that, under New York law, a final judgment
    of divorce ‘‘cannot [be] attack[ed] . . . based on a
    motion to open. It must be done by a plenary action, a
    contract action . . . .’’ Accordingly, the court rendered
    judgment in favor of the defendant.
    The plaintiff appealed from the judgment of the trial
    court to the Appellate Court, claiming, among other
    things, that the trial court improperly had applied ‘‘New
    York procedural rules, rather than Connecticut proce-
    dural rules, when it dismissed [her] motion.’’5 Gershon
    v. Back, supra, 
    201 Conn. App. 227
    . The Appellate Court
    disagreed, holding that ‘‘the New York rule requiring a
    plenary action to challenge the terms of a settlement
    agreement, incorporated but not merged into the judg-
    ment of dissolution, is substantive [for choice of law
    purposes].’’ 
    Id., 249
    . The Appellate Court reasoned that,
    under New York law, ‘‘[a] stipulation of settlement not
    merged into the judgment is independently binding on
    the parties, and New York courts may not impair the
    parties’ contractual rights under the agreement by modi-
    fying the divorce judgment.’’ 
    Id., 251
    . Because New York’s
    plenary action rule ‘‘affects the very existence of the cause
    of action,’’ the Appellate Court concluded that it was ‘‘sub-
    stantive and not procedural.’’ 
    Id., 253
    .
    Although the Appellate Court agreed ‘‘with the [trial]
    court’s conclusion that, under New York substantive
    law, the plaintiff was required to bring a plenary action’’;
    id.; it disagreed ‘‘with the [trial] court’s conclusion that
    it lacked subject matter jurisdiction.’’ 
    Id., 254
    . The
    Appellate Court observed that the trial ‘‘court had juris-
    diction to consider the motion to open pursuant to
    [General Statutes] §§ 46b-1 and 46b-71 (b)’’ and, there-
    fore, concluded that the trial court ‘‘should have denied,
    rather than dismissed, the motion to open.’’ Id. We sub-
    sequently granted the plaintiff’s petition for certification
    to appeal, limited to the following issue: ‘‘Did the Appel-
    late Court correctly determine that a New York law is
    substantive rather than procedural for choice of law
    purposes when that law would require a litigant in the
    parties’ circumstances who is seeking to obtain post-
    judgment relief in a marital dissolution case to file a
    plenary action rather than a motion to open the dissolu-
    tion judgment?’’ Gershon v. Back, 
    337 Conn. 901
    , 901–
    902, 
    252 A.3d 364
     (2021).
    On appeal to this court, the plaintiff claims that New
    York’s plenary action rule is procedural for choice of
    law purposes and, therefore, inapplicable to this Con-
    necticut action because it merely designates the means
    by which to vindicate her common-law contractual
    rights. The defendant responds that New York’s plenary
    action rule is substantive because the parties’ common-
    law contractual rights under the separation agreement
    are independent of the divorce judgment, and an order
    opening, modifying, or vacating the divorce judgment
    cannot affect those rights.6 For the reasons that follow,
    we agree with the defendant.
    ‘‘It is well settled that [c]hoice of law questions are
    subject to de novo review.’’ (Internal quotation marks
    omitted.) Reclaimant Corp. v. Deutsch, 
    332 Conn. 590
    ,
    599, 
    211 A.3d 976
     (2019). To determine whether New
    York or Connecticut law governs a motion to open
    and vacate a New York judgment of divorce registered
    pursuant to § 46b-71, we apply Connecticut’s conflict
    of law rules. See id. Subsection (b) of § 46b-71 codifies
    the conflict of law rules governing a foreign matrimonial
    judgment registered in this state and provides in rele-
    vant part that such a judgment ‘‘shall have the same
    effect and may be enforced or satisfied in the same
    manner as any like judgment of a court of this state
    and is subject to the same procedures for modifying,
    altering, amending, vacating, setting aside, staying or
    suspending said judgment as a judgment of a court of
    this state; provided, in modifying, altering, amending,
    setting aside, vacating, staying or suspending any such
    foreign matrimonial judgment in this state the substan-
    tive law of the foreign jurisdiction shall be controlling.’’
    The plaintiff’s motion to open and set aside the judg-
    ment is governed by New York substantive law and
    Connecticut procedural law.
    This approach is consistent with the Restatement
    (Second) of Conflict of Laws and the well established
    principle that, ‘‘in a choice of law situation the forum
    state will apply its own procedure . . . .’’ (Internal quo-
    tation marks omitted.) Reclaimant Corp. v. Deutsch,
    
    supra,
     
    332 Conn. 603
    . As we explained in Reclaimant
    Corp., under § 122 of the Restatement (Second), ‘‘ ‘[t]he
    forum has compelling reasons for applying its own
    rules’ to procedural issues, even if the substantive law
    of another jurisdiction applies, because, ‘in matters of
    judicial administration, it would often be disruptive or
    difficult . . . to apply the local rules of another state.
    The difficulties involved in doing so would not be repaid
    by a furtherance of the values that the application of
    another state’s local law is designed to promote.’ ’’ Id.,
    604, quoting 1 Restatement (Second), Conflict of Laws
    § 122, comment (a), p. 350 (1971).
    The line between substance and procedure is not
    always easily drawn. ‘‘[Although] there is no precise
    definition of either [substantive or procedural law], it
    is generally agreed that a substantive law creates,
    defines and regulates rights [whereas] a procedural law
    prescribes the methods of enforcing such rights or
    obtaining redress.’’ (Internal quotation marks omitted.)
    Weber v. U.S. Sterling Securities, Inc., 
    282 Conn. 722
    ,
    739, 
    924 A.2d 816
     (2007). Although procedural rules
    generally ‘‘relate to the remedy as distinguished from
    the right,’’ we have recognized that some rules are ‘‘so
    interwoven with . . . the cause of action as to become
    one of the congeries of elements necessary to establish
    the right . . . .’’ (Internal quotation marks omitted.)
    Reclaimant Corp. v. Deutsch, 
    supra,
     
    332 Conn. 604
    –605;
    see Thomas Iron Co. v. Ensign-Bickford Co., 
    131 Conn. 665
    , 669, 
    42 A.2d 145
     (1945) (foreign law is substantive
    when ‘‘the foreign remedy is so inseparable from the
    cause of action that it must be enforced to preserve
    the integrity and character of the cause [of action]’’
    (internal quotation marks omitted)). Section 122 of the
    Restatement (Second) eschews ‘‘unthinking adherence’’
    to formal labels such as ‘‘ ‘procedural’ ’’ and ‘‘ ‘substan-
    tive,’ ’’ and, instead, suggests that courts ‘‘face directly the
    question whether the forum’s rule should be applied.’’
    1 Restatement (Second), supra, § 122, comment (b), p.
    352. To determine whether the forum’s rule should be
    applied to rules that ‘‘fall into a gray area between issues
    relating primarily to judicial administration and those
    concerned primarily with the rights and liabilities of the
    parties,’’ § 122 instructs courts to consider the following
    factors: (1) ‘‘whether the issue is one to which the
    parties are likely to have given thought in the course
    of entering into the transaction’’; (2) ‘‘whether the issue
    is one [the] resolution [of which] would be likely to
    affect the ultimate result of the case’’; (3) ‘‘whether
    the precedents have tended consistently to classify the
    issue as ‘procedural’ or ‘substantive’ for [choice of law]
    purposes’’; and (4) ‘‘whether an effort to apply the rules
    of the judicial administration of another state would
    impose an undue burden [on] the forum.’’ Id., comment
    (a), pp. 351–52.
    With these principles in mind, we turn to New York’s
    plenary action rule and the principles on which it is
    based. Unlike Connecticut courts, New York courts do
    not review the provisions of a separation agreement to
    ensure that the agreement is fair and equitable to the
    parties prior to rendering a final judgment of divorce.
    Compare 
    N.Y. Dom. Rel. Law § 236
     (3) (McKinney Cum.
    Supp. 2021) (‘‘[a]n agreement by the parties, made
    before or during the marriage, shall be valid and
    enforceable in a matrimonial action if such agreement
    is in writing, subscribed by the parties, and acknowl-
    edged or proven in the manner required to entitle a
    deed to be recorded’’), with General Statutes § 46b-66
    (a) (court presented with separation agreement ‘‘shall
    inquire into the financial resources and actual needs
    of the parties . . . in order to determine whether the
    agreement of the parties is fair and equitable under all
    the circumstances’’). Whereas, in Connecticut, separa-
    tion agreements typically are merged into the final judg-
    ment of divorce after they have been approved by the
    court, in New York, separation agreements typically are
    not merged but, instead, survive the judgment.
    One reason why separation agreements typically are
    not merged into the final judgment of divorce in New
    York is to avoid placing the imprimatur of the court on
    the agreement and ‘‘misleading spouses into believing
    [that] such [agreements have been determined] to be
    valid . . . .’’ (Citation omitted.) Jaslow v. Jaslow, 75
    App. Div. 2d 876, 878, 
    427 N.Y.S.2d 292
     (1980). The
    principal reason for this practice, however, is to pre-
    serve the contractual rights of the parties to enforce
    the separation agreement in a separate civil action. An
    unmerged ‘‘separation agreement continues in effect as
    a separate and independent contractual arrangement
    between the parties . . . . Thus, a change in the divorce
    decree cannot modify the separation agreement absent
    a clear expression by the parties of such an intent.’’
    (Citations omitted.) Kleila v. Kleila, 
    50 N.Y.2d 277
    , 283,
    
    406 N.E.2d 753
    , 
    428 N.Y.S.2d 896
     (1980). The unmerged
    separation agreement ‘‘survives as a separate contract
    to which the parties are bound. Consequently, [although]
    a judgment of divorce can be attacked [by a postjudg-
    ment motion], the separation agreement will remain
    unimpeached unless challenged in a plenary action
    . . . .’’ (Citation omitted.) Lambert v. Lambert, 142
    App. Div. 2d 557, 558, 
    530 N.Y.S.2d 223
     (1988); see Fine
    v. Fine, 191 App. Div. 2d 410, 411, 
    594 N.Y.S.2d 309
    (1993) (‘‘The stipulation of settlement is an independent
    contract binding on the parties . . . and the court may
    not impair the plaintiff’s contractual rights under the
    agreement by modifying the divorce judgment . . . .
    The proper manner for the defendant to challenge the
    terms of the stipulation of settlement is in a plenary
    action . . . .’’ (Citations omitted.)). In a plenary con-
    tract action, the separation agreement is ‘‘subject to
    principles of contract construction and interpretation’’;
    (internal quotation marks omitted) In re Blonder v.
    Blonder, 171 App. Div. 3d 1043, 1045, 
    98 N.Y.S.3d 329
    (2019); instead of the principles governing divorce
    actions. See 
    N.Y. Dom. Rel. Law § 236
     (3) (McKinney
    Cum. Supp. 2021); see also Fine v. Fine, 26 App. Div.
    3d 406, 407, 
    810 N.Y.S.2d 211
     (2006) (‘‘[a] plenary action
    to vacate a stipulation of settlement on the basis of
    fraud . . . is not a matrimonial action’’ under New
    York Domestic Relations Law). Stated simply, the par-
    ties to an unmerged separation agreement have ‘‘vested
    contractual rights’’ that generally cannot be disturbed
    by a postjudgment motion in a divorce action.7 Kleila
    v. Kleila, 
    supra, 284
    .
    The plenary action rule is predicated, at least in signif-
    icant part, on New York’s strong public interest in the
    finality of judgments; see, e.g., Teitelbaum Holdings,
    Ltd. v. Gold, 
    48 N.Y.2d 51
    , 55–56, 
    396 N.E.2d 1029
    , 
    421 N.Y.S.2d 556
     (1979); and in encouraging parties to resolve
    their own interests through contractual arrangements.
    See, e.g., Bloomfield v. Bloomfield, 
    97 N.Y.2d 188
    , 193,
    
    764 N.E.2d 950
    , 
    738 N.Y.S.2d 650
     (2001) (‘‘there is a
    strong public policy favoring individuals ordering and
    deciding their own interests through contractual arrange-
    ments’’ (internal quotation marks omitted)); Christian
    v. Christian, 
    42 N.Y.2d 63
    , 71–72, 
    365 N.E.2d 849
    , 
    396 N.Y.S.2d 817
     (1977) (‘‘Generally, separation agreements
    [that] are regular on their face are binding on the parties,
    unless and until they are put aside . . . . Judicial
    review is to be exercised circumspectly, sparingly and
    with a persisting view to the encouragement of parties
    [to settle] their own differences in connection with the
    negotiation of property settlement provisions.’’ (Cita-
    tions omitted.)); Galusha v. Galusha, 
    116 N.Y. 635
    , 645–
    46, 
    22 N.E. 1114
     (1889) (‘‘the separation agreement was
    not affected by the decree granting an absolute divorce,’’
    in part because ‘‘[t]he law looks favorably [on] and
    encourages settlements made outside of [the] courts
    between parties to a controversy’’). As the New York
    Court of Appeals has observed, ‘‘[t]o rewrite a judgment
    of divorce [that] has been relied on by both parties . . .
    would defeat the [parties’] reasonable expectation that
    the judgment was valid as [rendered], and would sub-
    vert the policy of upholding settled domestic relations
    that underlies the doctrine of equitable estoppel in
    divorce cases . . . .’’ (Citations omitted.) Rainbow v.
    Swisher, 
    72 N.Y.2d 106
    , 110–111, 
    527 N.E.2d 258
    , 
    531 N.Y.S.2d 775
     (1988). Because ‘‘the provisions of a
    divorce judgment are considered final and binding on
    the parties . . . absent unusual circumstances or
    explicit statutory authorization’’; (internal quotation
    marks omitted) Sass v. Sass, 276 App. Div. 2d 42, 46,
    
    716 N.Y.S.2d 686
     (2000); see footnote 7 of this opinion;
    an unmerged separation agreement cannot be
    rescinded, vacated, or set aside by a postjudgment
    motion in a divorce action.
    Application of the four factors enumerated in com-
    ment (a) to § 122 of the Restatement (Second) leads
    us to conclude that New York’s plenary action rule is
    so interwoven with the plaintiff’s cause of action as
    to be deemed substantive. To begin, the unequivocal
    language employed by the parties in their separation
    agreement adopted in plain and forceful terms the very
    essence of New York’s plenary action rule. In addition
    to the choice of law provision’s adoption of New York
    law for ‘‘[a]ll matters affecting the execution, interpreta-
    tion, performance and enforcement of [the separation]
    [a]greement and the rights of the parties hereto,’’ the
    separation agreement expressly provides that it ‘‘shall
    not be invalidated or otherwise affected by any decree
    or judgment of separation or divorce made by any
    court in any action which may presently exist or may
    hereafter be instituted by either party against the other
    for a separation or divorce,’’ and adds—if that were
    not clear enough—that ‘‘the obligations and covenants
    of this [a]greement shall survive any decree or judg-
    ment of separation or divorce and shall not merge
    therein, and this [a]greement may be enforced inde-
    pendently of such decree or judgment.’’ (Emphasis
    added.) The separation agreement further provides that
    ‘‘no judgment, order or decree in any action for divorce
    or separation, whether brought in the [s]tate of New
    York, or in any other state or country having jurisdiction
    [over] the parties hereto, shall make any provisions
    for alimony or child support or affect the property
    rights of either party in a manner inconsistent with
    the provisions of this [a]greement . . . .’’ (Emphasis
    added.)
    The fact that the parties explicitly incorporated New
    York’s plenary action rule into their separation agree-
    ment by providing that their contractual rights could
    not be invalidated or affected by any final judgment of
    divorce ‘‘is a weighty reason for applying that law rather
    than the local law of the forum . . . .’’ 1 Restatement
    (Second), supra, § 122, comment (a), p. 351; see Boyd
    Rosene & Associates, Inc. v. Kansas Municipal Gas
    Agency, 
    174 F.3d 1115
    , 1126 (10th Cir. 1999) (‘‘[b]ecause
    parties are empowered to make contractual [choice of
    law] provisions, their expectations about the applicabil-
    ity of those [choice of law] provisions are a significant
    factor in the determination of whether an issue is sub-
    stantive or procedural for [choice of law] purposes’’).
    The remaining Restatement (Second) factors also
    weigh in favor of our conclusion that New York’s ple-
    nary action rule is substantive under these circum-
    stances. Application of New York’s plenary action rule
    will affect the ultimate substantive outcome of this case
    because, as the Appellate Court correctly determined,
    the parties ‘‘have contractual rights that . . . cannot
    be undone by modifying the judgment of dissolution.’’
    Gershon v. Back, supra, 
    201 Conn. App. 251
    –52; see,
    e.g., Goldman v. Goldman, 
    282 N.Y. 296
    , 305, 
    26 N.E.2d 265
     (1940) (modification of divorce judgment ‘‘[did] not
    relieve the defendant of any contractual obligation’’
    under separation agreement, and ‘‘the plaintiff [could]
    still resort to the usual remedies for breach of a contrac-
    tual obligation’’). Additionally, to our knowledge, there
    is no settled precedent classifying New York’s plenary
    action rule as procedural or substantive for choice of
    law purposes; the parties, at least, have not brought
    any such precedent to our attention, and we have found
    nothing of assistance in this regard. Nor will the applica-
    tion of the rule impose an undue burden on the courts
    of this state. Indeed, Connecticut courts have recog-
    nized that separation agreements are contracts that may
    be litigated independently of the divorce judgment in
    a civil contract action. See, e.g., Friedlander v. Fried-
    lander, 
    5 Conn. App. 1
    , 4, 
    496 A.2d 964
     (‘‘a separation
    agreement is enforceable in a civil suit on the con-
    tract’’), cert. denied, 
    197 Conn. 812
    , 
    499 A.2d 58
     (1985);
    Freeman v. Freeman, Superior Court, judicial district
    of Stamford-Norwalk, Docket No. CV-XX-XXXXXXX-S
    (April 6, 2010) (
    49 Conn. L. Rptr. 578
    , 580) (‘‘multiple
    Superior Court judges have determined that it is appro-
    priate to litigate a breach of a separation agreement in
    a civil action for breach of contract’’ (internal quotation
    marks omitted)); Lord v. Lord, Superior Court, judicial
    district of Fairfield, Docket No. CV-XX-XXXXXXX (August
    20, 2002) (
    33 Conn. L. Rptr. 88
    , 89) (separation agree-
    ments are ‘‘contracts . . . enforced by actions brought
    [on] the contracts themselves and the remedies are no
    other or different than the remedies provided by law
    for the breach of any other contract’’ (internal quotation
    marks omitted)). We therefore conclude that New York’s
    plenary action rule is substantive and that the Appellate
    Court correctly determined that the plaintiff’s motion
    to open and vacate the divorce judgment should have
    been denied.
    The plaintiff contends that New York’s plenary action
    rule is procedural under Baxter v. Sturm, Ruger & Co.,
    
    230 Conn. 335
    , 
    644 A.2d 1297
     (1994), and its progeny
    because the right to challenge a contract on the basis
    of fraud existed at common law.8 This argument miscon-
    strues our reasoning in the Baxter line of cases. In
    Baxter, we addressed whether Connecticut law treats
    another state’s statute of repose as substantive or proce-
    dural for choice of law purposes. 
    Id., 336
    . We deter-
    mined that a statute of repose, like a statute of limita-
    tions, ‘‘is considered one of the congeries of elements
    necessary to establish the right, and therefore charac-
    terized as substantive, only when it applies to a new
    right created by statute. . . . In such circumstances,
    [t]he time within which the suit must be brought oper-
    ates as a limitation of the liability itself as created [by
    the statute], and not of the remedy alone.’’ (Citations
    omitted; emphasis in original; internal quotation marks
    omitted.) 
    Id., 340
    . ‘‘If the right existed at common law,
    then the statute of repose is properly characterized as
    procedural because it functions only as a qualification
    on the remedy to enforce the preexisting right. If, how-
    ever, the right is newly created by the statute, then the
    statute of repose is properly characterized as substan-
    tive because the period of repose is so integral a part
    of the cause of action as to warrant saying that it quali-
    fie[s] the right.’’ (Internal quotation marks omitted.) 
    Id., 347
    ; see Reclaimant Corp. v. Deutsch, 
    supra,
     
    332 Conn. 608
     (‘‘[u]nder Connecticut’s choice of law rules, the
    dispositive inquiry is not whether the statute at issue
    properly is characterized as a statute of repose or a
    statute of limitations, but whether the nature of the
    underlying right that forms the basis of the lawsuit
    existed at common law’’ (internal quotation marks omit-
    ted)).
    Baxter and its progeny are inapposite for the simple
    reason that New York’s plenary action rule is not a
    statute of limitations or a statute of repose, and the
    distinction employed to distinguish between procedure
    and substance in that context has no application in the
    present case. In fact, the plenary action rule is not a
    creature of statute at all but, instead, an entrenched
    feature of New York’s common law for the past 100
    years. See Yonkers Fur Dressing Co. v. Royal Ins. Co.,
    Ltd., 
    247 N.Y. 435
    , 446, 
    160 N.E. 778
     (1928) (‘‘Defendants
    may be able in an independent suit to upset the settle-
    ment for reasons that would invalidate a contract, such
    as fraud or [overreaching]. But when a compromise
    results in the termination of an action and the execution
    of a new agreement giving effect to the settlement, it
    cannot be undone in the discretion of the court, on
    motion in the action and on conflicting affidavits rais-
    ing anew the same dispute once settled . . . .’’ (Empha-
    sis added.)). The plenary action rule draws ‘‘its justifica-
    tion from the practical notion that there must ultimately
    be an end to litigation’’ and requires ‘‘a plenary suit
    . . . [in which] the stipulation [of settlement] relates to
    an action [that] has previously terminated.’’ Teitelbaum
    Holdings, Ltd. v. Gold, supra, 
    48 N.Y.2d 55
    . It is properly
    characterized as a limitation on the right to challenge
    a separation agreement that is incorporated but not
    merged into a final judgment of divorce, rather than a
    mere limitation on the remedy, particularly because the
    parties explicitly incorporated the plenary action rule
    into the terms of their separation agreement and, by
    doing so, bargained for vested contractual rights that
    survive the final judgment of divorce.
    The judgment of the Appellate Court is affirmed.
    In this opinion the other justices concurred.
    1
    The defendant died on December 18, 2020, and the coexecutors of his
    estate, Adam Cotumaccio and Pamela Chupka, were substituted as defen-
    dants. All references to the defendant in this opinion are to Back.
    2
    General Statutes § 46b-71 provides: ‘‘(a) Any party to an action in which
    a foreign matrimonial judgment has been rendered, shall file, with a certified
    copy of the foreign matrimonial judgment, in the court in this state in which
    enforcement of such judgment is sought, a certification that such judgment
    is final, has not been modified, altered, amended, set aside or vacated and
    that the enforcement of such judgment has not been stayed or suspended,
    and such certificate shall set forth the full name and last-known address of
    the other party to such judgment and the name and address of the court in
    the foreign state which rendered such judgment.
    ‘‘(b) Such foreign matrimonial judgment shall become a judgment of the
    court of this state where it is filed and shall be enforced and otherwise
    treated in the same manner as a judgment of a court in this state; provided
    such foreign matrimonial judgment does not contravene the public policy
    of the state of Connecticut. A foreign matrimonial judgment so filed shall
    have the same effect and may be enforced or satisfied in the same manner
    as any like judgment of a court of this state and is subject to the same
    procedures for modifying, altering, amending, vacating, setting aside, staying
    or suspending said judgment as a judgment of a court of this state; provided,
    in modifying, altering, amending, setting aside, vacating, staying or sus-
    pending any such foreign matrimonial judgment in this state the substantive
    law of the foreign jurisdiction shall be controlling.’’
    3
    Under the final judgment of divorce, ‘‘[e]ach party has a right to seek a
    modification of the child support order upon a showing of: (i) a substantial
    change in circumstances; or (ii) that three years have passed since the order
    was entered, last modified or adjusted; or (iii) there has been a change in
    either party’s gross income by [15] percent or more since the order was
    entered, last modified, or adjusted; however, if the parties have specifically
    opted out [of] subparagraph (ii) or (iii) of this paragraph in a validly executed
    agreement or stipulation, then that basis to seek modification does not
    apply.’’ (Emphasis omitted.) See 
    N.Y. Dom. Rel. Law § 236
     (9) (b) (2) (i)
    (McKinney Cum. Supp. 2021) (‘‘[t]he court may modify an order of child
    support, including an order incorporating without merging an agreement
    or stipulation of the parties, upon a showing of a substantial change in
    circumstances’’); 
    N.Y. Dom. Rel. Law § 236
     (9) (b) (2) (ii) (A) and (B)
    (McKinney Cum. Supp. 2021) (‘‘[i]n addition, unless the parties have specifi-
    cally opted out of the following provisions in a validly executed agreement
    or stipulation entered into between the parties, the court may modify an
    order of child support where . . . three years have passed since the order
    was entered, last modified or adjusted; or . . . there has been a change in
    either party’s gross income by fifteen percent or more since the order was
    entered, last modified or adjusted’’). In its memorandum of decision on the
    plaintiff’s motion for modification, the trial court found that the parties
    clearly had not opted out of subparagraphs (ii) or (iii) in the separation
    agreement.
    4
    The defendant’s attached 2010 income information included his W-2 form
    from Flavormatic, which listed his wages and earnings as $150,000.
    5
    The plaintiff also claimed that the trial court ‘‘(1) improperly addressed
    the merits of the motion to open after determining that it lacked subject
    matter jurisdiction, (2) abused its discretion by failing to grant her motion
    for a continuance after her counsel disclosed that she intended to withdraw
    her appearance, and (3) erred in finding that the plaintiff had failed to
    demonstrate probable cause for postjudgment discovery under Oneglia . . .
    or comparable New York law.’’ Gershon v. Back, supra, 
    201 Conn. App. 227
    n.1. The Appellate Court did not address the plaintiff’s additional claims in
    light of its conclusion that ‘‘the plaintiff was required to raise her claims
    with respect to the parties’ [separation agreement] by means of a plenary
    action.’’ 
    Id.
    6
    The defendant also claims that this certified appeal is moot because the
    trial court’s judgment may be affirmed on the alternative ground that the
    plaintiff ratified the separation agreement and, therefore, is estopped from
    challenging it on the basis of fraud. ‘‘Undoubtedly, if there exists an unchal-
    lenged, independent ground to support a decision, an appeal from that
    decision would be moot, as this court could not afford practical relief even
    if the appellant were to prevail on the issue raised on appeal.’’ Hartford v.
    CBV Parking Hartford, LLC, 
    330 Conn. 200
    , 210, 
    192 A.3d 406
     (2018). To
    render an appeal moot, however, the unchallenged ground must be indepen-
    dent of the issue on appeal, meaning that resolution of the issue on appeal
    would not and could not affect a separate unchallenged basis on which to
    affirm the underlying judgment. See 
    id.,
     211–12 (appeal was not moot
    because trial court’s factual finding regarding valuation of property was
    not independent of issue on appeal). In the present case, the trial court’s
    resolution of the ratification issue was not independent of its resolution of
    the choice of law question because the trial court’s application of New York
    law to the plaintiff’s request for postjudgment discovery led it to conclude
    that the plaintiff had produced insufficient evidence of fraud and, therefore,
    was estopped from challenging the agreement. See, e.g., Brennan v. Bren-
    nan, 305 App. Div. 2d 524, 525, 
    759 N.Y.S.2d 744
     (2003) (concluding that
    separation agreement had been ratified in absence of evidence of fraud);
    Wilson v. Neppell, 253 App. Div. 2d 493, 494, 
    677 N.Y.S.2d 144
     (same), appeal
    denied, 
    92 N.Y.2d 816
    , 
    706 N.E.2d 747
    , 
    683 N.Y.S.2d 759
     (1998); Shalmoni
    v. Shalmoni, 141 App. Div. 2d 628, 629, 
    529 N.Y.S.2d 538
     (same), appeal
    dismissed, 
    73 N.Y.2d 851
    , 
    534 N.E.2d 333
    , 
    537 N.Y.S.2d 495
     (1988); see also
    Ronson v. Ronson, 58 App. Div. 2d 987, 988, 
    396 N.Y.S.2d 939
     (1977) (‘‘In
    order to vitiate the support agreement, [a party] is required to show facts
    in evidentiary form. Conclusory assertions of fraud are insufficient . . . .’’
    (Citations omitted.)). Because the choice of law and ratification issues are
    related, we conclude that the plaintiff’s appeal is not moot.
    7
    There are some exceptions to the plenary action rule, none of which is
    applicable to the present appeal. See, e.g., 
    N.Y. Dom. Rel. Law § 236
     (9) (b)
    (1) (McKinney Cum. Supp. 2021) (‘‘[w]here, after the effective date of this
    part, an agreement remains in force, no modification of an order or judgment
    incorporating the terms of said agreement shall be made as to maintenance
    without a showing of extreme hardship on either party, in which event
    the judgment or order as modified shall supersede the terms of the prior
    agreement and judgment for such period of time and under such circum-
    stances as the court determines’’); 
    N.Y. Gen. Oblig. Law § 5-311
     (McKinney
    2022) (‘‘Except as provided in section two hundred thirty-six of the domestic
    relations law, a husband and wife cannot contract to alter or dissolve the
    marriage or to relieve either of his or her liability to support the other in
    such a manner that he or she will become incapable of self-support and
    therefore is likely to become a public charge. An agreement, heretofore or
    hereafter made between a husband and wife, shall not be considered a
    contract to alter or dissolve the marriage unless it contains an express
    provision requiring the dissolution of the marriage or provides for the pro-
    curement of grounds of divorce.’’); 
    N.Y. Jud. Ct. Acts § 463
     (McKinney 2008)
    (‘‘[a] separation agreement does not preclude the filing of a petition and
    the making of an order under section four hundred forty-five of this article
    for support of a spouse who is likely to become in need of public assistance
    or care’’); see also footnote 3 of this opinion.
    8
    The plaintiff also contends that the plenary action rule is procedural
    because the failure to commence a plenary action is not always treated as
    a fatal defect in New York. In support of this contention, the plaintiff relies
    on cases from the Appellate Division of the New York Supreme Court that
    recognized the plenary action rule but, in the interest of judicial economy,
    nonetheless addressed the merits of a postjudgment motion challenging an
    unmerged separation agreement when the lower court had conducted ‘‘a
    full hearing tantamount to a plenary trial . . . .’’ Gaines v. Gaines, 188 App.
    Div. 2d 1048, 1048, 
    592 N.Y.S.2d 204
     (1992); accord Verna v. Verna, 134
    App. Div. 3d 1438, 1438, 
    23 N.Y.S.3d 500
     (2015); Dunham v. Dunham, 214
    App. Div. 2d 961, 961, 
    626 N.Y.S.2d 932
     (1995); Culp v. Culp, 117 App. Div.
    2d 700, 702, 
    498 N.Y.S.2d 846
     (1986). The plaintiff argues that these cases
    stand for the proposition that the plenary action rule is procedural because,
    ‘‘[if] the rule [was] substantive, the court would have [had] no authority’’
    to adjudicate the postjudgment motion. We reject the plaintiff’s claim
    because there is a fundamental distinction between the authority of a court
    to adjudicate a cause of action and the court’s determination of the substan-
    tive law governing that cause of action. See Lacks v. Lacks, 
    41 N.Y.2d 71
    ,
    74, 77, 
    359 N.E.2d 384
    , 
    390 N.Y.S.2d 875
     (1976). As the New York Court of
    Appeals explained in Lacks, the ‘‘[subject matter] jurisdiction-competence’’
    of the courts should not be confused with the ‘‘substantive elements of a
    cause for relief’’ because ‘‘[t]o do so would be to undermine significantly
    the doctrine of res judicata, and to eliminate the certainty and finality in
    the law and in litigation which the doctrine is designed to protect.’’ Id., 77.
    Thus, the nonjurisdictional nature of the plenary action rule does not resolve
    the issue of whether the rule is substantive or procedural for choice of
    law purposes.