It's a living legal community making laws accessible and interactive. Click Here to get Started »
Voluntary sexual relations between an individual who is married and someone who is not the individual's spouse.
Adultery is viewed by the law in many jurisdictions as an offense injurious to public morals and a mistreatment of the marriage relationship.
Statutes attempt to discourage adultery by making such behavior punishable as a crime and by allowing a blameless party to obtain a divorce against an adulterous spouse.
Although adultery has been historically regarded as a legal wrong, it has not always been considered a crime. In Europe during the fifteenth and sixteenth centuries, adultery was punishable solely in courts created by the church to impose good morals. In the ecclesiastical courts, adultery was any act of sexual intercourse by a married person with someone not his or her spouse. The act was considered wrongful regardless of whether the other person was married. At common law, adultery was wrongful intercourse between a married woman and any man other than her husband.
Several state legislatures statutorily prohibit adultery as a crime. Under some statutes, both parties to an adulterous relationship are guilty of a crime if either of them is married to someone else. Other statutes provide that the act is criminal only if the woman is married.
Under the law of many states, a single act of adultery constitutes a crime, whereas in others, there must be an ongoing and notorious relationship. The punishment set by statute may be greater for an individual who engages in repeated acts of adultery than for one who commits an isolated act.
Defenses An individual who has been charged with committing adultery may have a valid legal defense, such as the failure or physical incapacity to consummate the sex act.
A woman is not guilty of adultery if the sex act resulted from rape. Some states recognize ignorance of the accused regarding the marital status of his or her sexual partner as a defense. In a few jurisdictions only the married party can be prosecuted for adultery. If the other party to the relationship is not married, he or she may be prosecuted for fornication instead of adultery.
Initiation of Criminal Proceedings Under some statutes, a prosecution for adultery can be brought only by the spouse of the accused person although technically the action is initiated in the name of the state. Other states provide that a husband or wife is precluded from commencing prosecution for adultery since those states have laws that prohibit a husband or wife from testifying against his or her spouse. In such states, a complaint can be filed by a husband or wife against the adulterous spouse's lover.
Evidence Customary rules prescribe the types of evidence that can be offered to prove guilt or innocence. There must be a showing by the prosecutor that the accused party and another named party had sexual relations. Depending on state statutes, the prosecutor must show that either one or both parties to the adultery were wed to someone else at the time of their relationship.
Evidence that the defendant had the chance to have sexual relations coupled with a desire, or opportunity and inclination, might be sufficient to prove guilt. Photographs or testimony of a witness who observed the couple having sexual intercourse is not necessary. The fact that a married woman accused of adultery became pregnant during a time when her husband was absent might be admissible to demonstrate that someone other than her spouse had the opportunity of engaging in illicit sex with her.
Letters in which the accused parties have written about their amorous feelings or clandestine encounters may be introduced in court to support the assertion that the parties had the inclination to engage in sexual relations. Character evidence indicating the good or bad reputation of each party may be brought before the jury. Evidence of a woman's sexual relationships with men other than the party to the adultery generally cannot be used; however, if her reputation as a prostitute can be demonstrated, it may be offered as evidence.
Suspicious activities and incriminating circumstances may be offered as circumstantial evidence.
Enforcement of Statutes
Although the District of Columbia and approximately half of the states continue to have laws on the books criminalizing adultery, these laws are rarely invoked. Traditionally, states advanced three goals in support of their adultery laws: (1) the prevention of disease and illegitimate children; (2) the preservation of the institution of marriage; and (3) the safeguarding of general community morals.
Courts in the jurisdictions still prohibiting adultery have openly questioned whether adultery laws in fact serve these goals. The Florida Supreme Court, for example, found that adultery statutes bear no rational, much less compelling, relationship to disease prevention. The court said that the risk of contracting disease is already a greater deterrent to extra-marital sex than criminal punishment. The court also noted that the fear of prosecution prevents infected people from voluntarily seeking treatment. Purvis v. State, 377 So. 2d 674, 677 (Fla. 1979).
At the same time, many prosecutors began to realize that once the act of adultery is committed, the harm to the marriage is for the most part complete, especially if the infidelity is disclosed or discovered. In other words, after a spouse has been unfaithful, there is little the judicial system can offer to undo the act and reverse the damage. Thus, prosecutors have increasingly questioned whether prosecuting the adulterer will do much if anything to preserve the marriage.
Finally, judges, prosecutors, and other state officials have increasingly realized that prosecutions for adultery have had little practical effect in "safeguarding the community morals." Opinion polls consistently show that significant numbers of spouses admit to cheating on their partners during marriage. In light of the growing evidence that adultery laws no longer serve their three underlying purposes, most state prosecutors have made a conscious decision against wasting their scarce resources on prosecuting alleged adulterers.
In states that still have adultery laws on the books, but have failed to prosecute anyone under them recently, courts have ruled that the mere lack of prosecution under the adultery statute does not result in that statute becoming invalid or judicially unenforceable. Courts have also rejected the argument that prosecutions for adultery are inconsistent with the right to privacy guaranteed by state and federal constitutions. Commonwealth v. Stowell, 389 Mass 171, 449 NE2d 357 (Mass 1983).
As a Defense
Occasionally, adultery has been successfully asserted as a defense to the crime of murder by an individual charged with killing his or her spouse's lover. Courts are loath, however, to excuse the heinous crime of murder on the ground that the accused party was agitated about a spouse's adulterous activities. However, individuals who kill their spouse after catching him or her committing adultery may be able to rely on a heat of passion defense, and thereby face prosecution or conviction for manslaughter, rather than first degree murder.
Based on the state's interest in the marital status of its residents, all legislatures had traditionally assigned statutes enumerating the grounds on which a divorce would be granted. These grounds, listed separately in the laws of each jurisdiction, generally included desertion, nonsupport, and adultery.
The basis of adultery as a ground for divorce has been discussed in various cases. There is an overriding public policy in favor of preserving the sanctity of marital relationships and family unity and a fear that adultery will serve to undermine these societal objectives.
Late twentieth-century changes in divorce laws, primarily the enactment of no-fault divorce statutes in many states, have made it easier for couples seeking divorce to end their marriages without having to prove adultery or any other ground. In the past many unhappy couples resorted to trickery to attempt to obtain a divorce through staging the discovery of allegedly adulterous conduct.
Nonetheless, adultery still may be relevant to divorce proceedings in which alimony is an issue. In twenty-seven states plus Puerto Rico and the District of Columbia, fault is one factor which courts will consider in deciding whether to award alimony. If the spouse seeking an alimony award committed adultery, he or she will have a more difficult time convincing the court that he or she is entitled to alimony than if he or she had not been unfaithful.
Friedman, Lawrence M. 2000. "A Dead Language: Divorce Law and Practice Before No-fault." Virginia Law Review 86 (October): 1497–1536.
Haggard, Melissa Ash. 1999. "Adultery: A Comparison of Military Law and State Law and the Controversy This Causes Under Our Constitution and Criminal Justice System." Brandeis Law Journal 37 (spring): 469–83.