Man and woman hugging, the man trying to kiss another woman.

Can Adultery Be Punished in a Prenuptial or Postnuptial Agreement?

For more than 50 years since adopting the Uniform Dissolution of Marriage Act (UDMA) in 1971, we have had no-fault divorces in Colorado, and that means the traditional grounds for divorce, including adultery, are abolished. Does that mean an infidelity clause in prenup or postnup agreements is enforceable? Can spouses introduce “fault” in their prenup or postnup? Colorado will very likely not uphold infidelity or other misconduct clauses in marital agreements, agreements, as discussed below.

A couple of states have allowed spouses to “opt-in” to fault-based divorce with covenant marriages, not only is this a tiny movement, but an agreement to modify the grounds for a divorce would contravene the Uniform Premarital and Marital Agreements Act (UPMAA), specifically C.R.S. 14-2-310(2) which provides:

“A term in a premarital agreement or marital agreement is not enforceable to the extent that it:… (c) purports to modify the grounds for a court-decreed legal separation or marital dissolution available under the law of this state.”

Spouses or would-be spouses can do a lot with marital agreements – for more information, see our articles in the Colorado Family Law Guide on prenuptial agreements and postnuptial agreements. But such agreements are intended to address financial issues, and whether a so-called “bad boy” clause would be upheld in Colorado is very much in doubt.

Lifestyle Clauses in Prenups or Postnups

Every so often news leaks of “unique” clauses in celebrity prenuptial agreements. Jessica Simpson and former Dallas Cowboy quarterback apparently had a prenup which penalized her for every pound she weighed over 135 pounds. Jay Z apparently agreed to pay Beyonce $5m for each child she bore. Humorous, but it would be astonishing if family law courts actually upheld some of these absurd terms.

For more information about lifestyle clauses in celebrity marital agreements, see this American Bar Association gallery Love Hurts: 13 Famous Prenups. But while these may appear humorous to us, to spouses in a difficult or emotional situation, a clause penalizing misconduct may be the only sure way to save a marriage which is otherwise headed for divorce.

From the published cases, it appears that fault-based marital agreement clauses are more common in post-nuptial agreements than in prenups. The typical scenario is that one spouse is caught cheating, using drugs, abusing alcohol, etc, and promises to change. The spouses then write up a marital agreement that includes the lifestyle requirement, and has financial penalties for the spouse who strays and commits what the agreement defines as misconduct.

A clause attempting to prevent “misconduct” by the other may be referred to by various terms, including:

  • Infidelity clause
  • Misconduct clause
  • Behavior clause
  • Lifestyle clause
  • Fault clause
  • “Bad Boy” or “Bad Girl” clause
  • Adultery clause
  • Cheating clause

And so on. There are probably other terms I came across while researching this issue that I’ve already forgotten, but the above list covers most cases.

Infidelity Clause in Prenup, or Punishing a Cheating Spouse

So are infidelity clauses or other lifestyle clauses in marital agreements legally enforceable in Colorado? Very likely not.

Prenuptial marriage agreement with a court gavel

Until it was repealed in 2013 by Colorado HB 13-1166, Colorado had a statute which, in theory, prohibited adultery. The former C.R.S. 18-6-501 read: “Adultery. Any sexual intercourse by a married person other than with that person’s spouse is adultery, which is prohibited.” But there was no penalty prescribed, and no known adultery prosecutions in decades.

The National Conference of Commissioners on Uniform State Laws, which promulgated the Uniform Premarital and Marital Agreements Act believe that infidelity clauses are generally not enforceable. The Official Comment to UPMAA section 10 (C.R.S. 14-2-310) states (case citations omitted from quote):

“There is a general consensus in the caselaw that courts will not enforce premarital agreement provisions relating to topics beyond the parties’ financial obligations inter se. And while some courts have refused to enforce provisions in premarital agreements and marital agreements that regulate (or attach financial penalties to) conduct during the marriage, this act does not expressly deal with such provisions, in part because a few courts have chosen to enforce premarital agreements relating to one type of marital conduct: parties’ cooperating in obtaining religious divorces or agreeing to appear before a religious arbitration board. Also, while there appear to be scattered cases in the distinctly different context of separation agreements where a court has enforced the parties’ agreement to avoid fault grounds for divorce, there appears to be no case law enforcing an agreement to avoid no-fault grounds. This act follows the position of the American Law Institute (Principles of the Law of Family Dissolution, Section 7.08(1) (2002)), that agreements affecting divorce grounds in any way should not be enforceable.”

This appears to be true. Although research has uncovered four states in the past few decades which have upheld infidelity clauses in pre- or post-nuptial agreements, none of these states have adopted the UPMAA (which states that a marital agreement may not modify the grounds for a divorce, and three of those states allow fault-based divorces as well as no-fault divorces.

So with the caveat that we are Colorado family law attorneys, and cannot keep on top of the laws of all 50 states when it comes to adultery and marital agreements, here are the cases from other states addressing infidelity clauses in marital agreements. Note I limited my research to cases from 1984 onwards, which is after the UPAA was promulgated and more of the “modern era” when it comes to dissolution of marriage.

States Allowing Fault or Adultery in a Marital Agreement

There is only one state I’ve found which is no-fault only (i.e. does not also allow fault-based divorce) but nonetheless upheld an infidelity clause in a prenup or postnup. In 2012, the Florida Court of Appeal upheld a prenuptial agreement clause by which the wife waived alimony unless one of several fault grounds, including adultery, was the basis of the divorce. Weymouth. This case is distinguishable in two regards from the traditional infidelity clause:

  • It required the more affluent spouse to pay for his fault, rather than trying to control the behavior of the poorer spouse by depriving her of alimony for adultery.
  • The fault would not deprive either spouse of anything, but instead adultery would simply put spousal support back in the hands of the court, applying normal state law provisions as happens in virtually every other case.

Four other states have either upheld infidelity clauses, or suggested that they would be upheld, but unlike Colorado, all three of these states also already allow spouses to put on evidence of fault in divorces, despite being no-fault states. In chronological order, these decisions are:

  • Ohio 1984. Gross. The court did not actually uphold an infidelity clause, but the court rejected one spouse’s argument that the other spouse’s adultery should void the agreement, saying the parties should have included such a clause in the agreement if they wanted one. Per Ohio Rev. Code § 3105.01(C), fault-based divorce, including adultery, is permitted in that state.
  • Pennsylvania 1993. Laudig. The court upheld a postnup clause by which the wife gave up all marital property rights in return for a lump sum payment if she committed adultery. Per 23 Pa. C.S. § 3301(a)(2), fault-based divorce, including for adultery, is permitted in that state.
  • Alabama 2008. Hubbard. As in the Gross case from Ohio, the court did not actually uphold an infidelity clause, but rejected a spouse’s argument that infidelity voided the agreement, since the parties could have simply included such a clause if that was their intent. Per Ala. Code § 30-2-1(a)(2), fault-based divorce, including for adultery, is permitted in that state.
  • Maryland 2022. Lloyd. In an unpublished opinion, the court upheld an infidelity clause in a “reconciliation” postnuptial agreement, signed after the husband cheated on the wife, under which he would owe her a $7 million lump sum for a variety of misconduct, including “”adultery, buggery or sodomy”. Spouses in Maryland can bypass the 12-month waiting period for a divorce if there is fault, and per Md. Code, Fam. Law § 7-103(a)(1) adultery is a ground for fault-based divorce.

So Florida is the only outlier – a state which does not normally allow fault-based grounds for divorce, but has nonetheless upheld a prenup provision where adultery would affect the financial settlement. But even there, adultery would simply mean returning to the statutory domestic relations law instead of deviating further from the norm to “punish” a spouse.

States Rejecting Infidelity Clause in Prenup or Postnup

Here are the states which have rejected attempts to enforce infidelity clauses in marital agreements:

  • California 2002. Diosdado. Penalty clause “in direct contravention of the public policy underlying no-fault divorce.”
  • Iowa 2009. Cooper. Allowing fault to affect financial settlement in a marital agreement “would empower spouses to seek an end-run around our no-fault divorce laws.”
  • Nevada 2018. Parker. (No link but discussed in Crofford. However, here the penalty clause voided was only for alimony, not property).
  • Hawaii 2022. Crofford. “Because the agreements require the family court to make determinations of fault, they violate Hawai‘i’s policy of no-fault divorce.”

In Diosdado, the California Court of Appeal took issue with infidelity clauses trying to regulate morals or fault:

“The family law court may not look to fault in dissolving the marriage, dividing property, or ordering support. Yet this agreement attempts to penalize the party who is at fault for having breached the obligation of sexual fidelity, and whose breach provided the basis for terminating the marriage. This penalty is in direct contravention of the public policy underlying no-fault divorce.

To be enforceable, a contract must have a ‘lawful object.’ A contract is unlawful if it is contrary to an express provision of law, contrary to the policy of express law, or otherwise contrary to good morals. Here, where the agreement attempts to impose a penalty on one of the parties as a result of that party’s ‘fault’ during the marriage, it is contrary to the public policy underlying the no-fault provisions for dissolution of marriage. For that reason, the agreement is unenforceable.”

Diosdado, at 496-97 (Cleaned Up).

And the Iowa Supreme Court does not want family law courts to delve into spouses’ sexual practices, and voided an infidelity clause in what they referred to as a “reconciliation agreement” (i.e. a postnup):

“The relationship between spouses cannot be regulated by contracts that are plead and proved in the courts as if the matter involved the timely delivery of a crate of oranges. We do not wish to create a bargaining environment where sexual fidelity or harmonious relationships are key variables.

Further, like our predecessors, we reject the idea of injecting the courts into the complex web of interpersonal relationships and the inevitable he-said-she-said battles that would arise in contracts that can be enforced only through probing of the nature of the marital relationship. Indeed, our no-fault divorce law is designed to limit acrimonious proceedings. Further, a contrary approach would empower spouses to seek an end-run around our no-fault divorce laws through private contracts.

As a result, we hold that the reconciliation agreement in this case is void. We further believe that as a void contract, it should be given no weight in the dissolution proceedings. We recognize that Iowa Code section 598.21(1)(k) and (m) authorizes the court to consider any written agreements and other factors that the court determines to be relevant. We, nevertheless, conclude that these statutory provisions do not extend to agreements between spouses that are void, such as the one presented here, because they intrude on the intimacies of the marital relationship and inject fault back into dissolution proceedings.”

Cooper, at 586-87 (Cleaned Up).

The rationale of the decisions rejecting fault clauses in postnuptial or prenuptial agreements more closely mirrors what I would expect from a family law judge in modern Colorado, which abolished fault-based divorce to avoid the unseemly prospect of having people spy on spouses through bedroom windows.

Can I Get an Infidelity Clause in My Post-Nup or Prenup?

We at Graham.Law have, on rare occasion, seen infidelity clauses which punish adultery in prenuptial or postnuptial agreements, but thus far, have not had occasion to litigate their enforceability as adultery was not alleged in those cases.

C.R.S. 14-2-310(2) provides that a specific “term” in an agreement would not be enforceable if it violated the various provisions of that statute, not that the entire agreement is voided. So it may be possible to include a standalone infidelity clause in a postnup which was not an integral part of the agreement.

Though there is no reported decision in Colorado addressing infidelity clauses in a prenuptial agreement, I doubt they would be enforceable. So while we would recommend against having an infidelity clause, there may be no harm in trying to penalize adultery. Or, there may be harm. By trying to punish marital “misconduct”, you risk incurring the ire of a judge who views it as overreaching and starts to question whether the entire agreement was the result of overreaching or undue pressure.

If you are thinking about risking an infidelity clause with the hope that it may at least deter adultery (see this Forbes article for a discussion), even if a court does not ultimately uphold it, then a few cautions. The marital agreement:

  • Should not be an abstract attempt to regulate marital behavior in a prenup, but be in a postnup as a result of actual adultery during the marriage.
  • Must be limited to property, where an agreement can be upheld if unconscionable, rather than trying to punish an adulterous spouse through alimony, which C.R.S. 14-10-114(2) expressly states “shall be made without regard to marital misconduct.”
  • Would need a good “severability clause” which provides that if the infidelity clause is held not enforceable, it has no impact on the legality of the rest of the agreement.

That’s a lot of caveats for a clause unlikely to survive judicial scrutiny, so a prudent person would focus on what a prenup or postnup can lawfully accomplish, rather than risking it all by trying to control your spouse’s behavior or punish adultery.

Defining Adultery in a Postnup

If you were to consider an infidelity clause, you would also need to consider what would constitute adultery – actual sexual intercourse, or other physical acts such as kissing, cuddling, etc? What level of proof would be required? Admission or photos? Or just inference from romantic texts? And how about emotional relationships where a person may love another and bear their soul, but the relationship was not physical

Adultery May Have Limited Role in No-Fault State

Even without an infidelity clause, while Colorado is a no-fault state, once in a while facts behind a spouse’s adultery may be relevant to the trial:

  • If one spouse spent significant marital funds entertaining or on gifts for a girlfriend/boyfriend, a court may find that to be dissipation of assets (which means spending funds on an improper purpose in anticipation of divorce), and award the aggrieved spouse an “offset”, or comparable funds to make up for it.
  • If a spouse’s significant other has a criminal history or could otherwise be dangerous, then that fact, and not the fact of adultery, could be relevant in a parenting case.

Delaying Acting on Adultery

Finally, if you ignore our advice and still include an infidelity clause, you cannot learn of adultery, and then do nothing. Or, worse, cheat yourself. Back during the days of “fault” divorces, some states had concepts such as “forgiven adultery” or “condoned adultery”, by which a spouse waived the right to claim adultery by the other spouse if he learned of it, and did not act on it at the time, or even forgave it.

And the UPMAA similarly has a section, C.R.S. 14-2-311, stating that equitable defenses such as “laches and estoppel”, apply to challenges to marital agreements. This means (no pun intended), if you “sleep on your rights”, you may lose the right to enforce an anti-adultery clause.

FAQ – Infidelity Clause in Prenup or Postnup Agreements

What is a postnuptial agreement?

A postnuptial agreement can be thought of as a prenup after marriage. Referred to as a “reconciliation agreement” in some states, it is an agreement spouses enter into during marriage with the intent to remain married which regulate financial issues should they divorce in the future.

What is an infidelity clause?

An infidelity clause in a prenup or a postnup is a clause by which a spouse who commits adultery gives up financial benefits upon divorce. Their legality is questionable, with no Colorado cases on point, but recent decisions from other no-fault states reject their enforceability.

Is adultery a crime?

Adultery is not a crime in Colorado. The statute which had previously prohibited adultery had not seen a prosecution in decades, and was finally repealed in 2013. However, the military still criminalizes adultery in some circumstances under Article 134 of the Uniform Code of Military Justice.

Does adultery affect alimony?

No. Even if spouses tried to have an “infidelity clause” in a prenup or postnup which prohibited adultery, under Colorado law an alimony award “shall be made without regard to marital misconduct.”

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