A crime against nature is a criminal charge, still used in many state codes, for sexual acts the law historically labeled “unnatural.” After the Supreme Court’s 2003 decision in Lawrence v. Texas, the phrase no longer reaches private, consensual sex between adults. What it still covers today is bestiality, necrophilia, any sexual conduct involving minors or coercion, and sexual acts performed in public. Convictions typically carry felony-level prison time, and in many jurisdictions they also require sex offender registration and trigger immigration, employment, and housing consequences that outlast the sentence itself.
What the Phrase Covers Today
At common law, “crime against nature” was essentially a synonym for sodomy and covered oral and anal sex regardless of the genders involved. Legislatures later expanded the term in some states to include bestiality and necrophilia. The phrase was never a consistent legal category; it reflected moral and religious judgments about sex, which is why its meaning shifted from state to state.
Many states still use the exact phrase in their criminal codes. Others replaced it with more specific statutes aimed at particular conduct. Roughly a dozen states have never formally repealed their old sodomy or crime-against-nature laws, so the language is still on the books even where it can no longer be enforced against consensual adult conduct. Older convictions under these statutes can still carry consequences, which is why the term matters even in states that have moved on from it.
What Lawrence v. Texas Took Off the Table
Lawrence v. Texas is the case that reshaped this entire area of law. The Supreme Court held in 2003 that a Texas statute criminalizing same-sex sexual conduct violated the Due Process Clause of the Fourteenth Amendment. The Court recognized a constitutionally protected liberty interest in intimate, consensual sexual conduct between adults, describing it as part of the “autonomy of self that includes freedom of thought, belief, expression, and certain intimate conduct.”1Justia Law. Lawrence v. Texas, 539 U.S. 558 (2003) The ruling invalidated sodomy laws across the country.
The Court drew its limits carefully. The majority stated that the case “does not involve minors, persons who might be injured or coerced, those who might not easily refuse consent, or public conduct or prostitution.”1Justia Law. Lawrence v. Texas, 539 U.S. 558 (2003) Everything outside that protected zone remains fair game for state criminal law, and that is where modern crime-against-nature prosecutions live.
Conduct That Is Still Criminal
Four broad categories of conduct continue to be prosecuted, whether under the old “crime against nature” label or under newer, more specific statutes.
Bestiality
Sexual contact with animals is illegal in nearly every state. Recent counts put roughly 49 states as having some criminal provision addressing it. West Virginia is often cited as the last state without a specific statute, though prosecutions there may still be possible under general animal cruelty laws. Depending on the state and the circumstances, bestiality can be charged as a misdemeanor or a felony. Newer statutes tend to be framed around animal protection rather than the older moral-offense language.
Necrophilia
Sexual acts involving a deceased person are criminalized in most states, either under a specific necrophilia statute or under broader abuse-of-a-corpse laws. Penalties usually track mid-range felonies, with prison sentences commonly falling in the one-to-ten-year range. Some states treat it as a distinct sex offense; others fold it into desecration-of-remains statutes.
Minors, Coercion, and Non-Consent
Sexual conduct involving force, coercion, or a person who cannot legally consent is criminal everywhere. That includes sexual contact with minors, acts against incapacitated people, and any conduct that lacks affirmative consent. These offenses generally carry the most severe penalties in the criminal code, and Lawrence expressly left states free to regulate them.
Public Sexual Conduct
Sexual acts performed in public can be prosecuted as indecent exposure, public lewdness, or similar offenses even when the participants are consenting adults. The privacy framework Lawrence built assumes conduct in private, so public sexual behavior gets no constitutional protection.
Where the Charge Can Come From
State law does most of the work here, but two other sources of criminal exposure often catch people off guard.
Federal Land
Under the Assimilative Crimes Act, conduct that occurs on federal property, such as military bases, national parks, and federal buildings, can be prosecuted under the criminal law of the surrounding state when no federal statute directly covers the behavior.2Office of the Law Revision Counsel. 18 U.S. Code 13 – Laws of States Adopted for Areas Within Federal Jurisdiction If a state’s crime-against-nature statute reaches bestiality, that state law can be enforced against conduct on a federal enclave within that state. Federal courts have upheld this approach.3United States Department of Justice Archives. 667. Assimilative Crimes Act, 18 U.S.C. 13
Federal Animal Cruelty Law
The PACT Act criminalizes “animal crushing” in interstate commerce or within federal jurisdiction.4Office of the Law Revision Counsel. 18 U.S. Code 48 – Animal Crushing The statute’s congressional findings reference “extreme acts of animal cruelty that appeal to a specific sexual fetish,” and it prohibits the creation and distribution of animal crush videos. The law does not use the word bestiality, but it offers a federal path for prosecuting certain forms of sexual animal abuse, especially when recorded and distributed.
Penalties on Conviction
Sentences vary sharply by jurisdiction and by the specific offense charged. Most crime-against-nature charges that can still be brought today carry serious consequences.
- Felony convictions commonly carry prison sentences of one to ten years, with longer terms available for aggravated offenses involving minors or extreme cruelty.
- Fines can reach several thousand dollars and are typically imposed alongside incarceration or probation.
- Where an offense is classified as a misdemeanor, or where mitigating factors exist, courts may impose probation, community service, or shorter jail terms instead of prison.
Judges weigh the defendant’s criminal history, the specific conduct, and any harm caused. A first bestiality offense might result in probation in one state and a multi-year prison sentence in another.
Sex Offender Registration
Registration is often the most durable part of a conviction. Under the federal Sex Offender Registration and Notification Act, offenders are classified into three tiers based on the severity of the offense. Minimum registration periods are 15 years for Tier I, 25 years for Tier II, and lifetime for Tier III.5Federal Register. Office of the Attorney General – The National Guidelines for Sex Offender Registration and Notification States can, and often do, impose longer periods.
Whether a crime-against-nature conviction triggers registration depends on how the state classifies the specific offense. SORNA’s tier definitions center on offenses comparable to federal sexual abuse statutes and offenses involving minors, rather than listing every state crime by name. Some states independently require registration for bestiality convictions; others do not. Registration restricts where you can live and work, requires regular reporting to law enforcement, and makes the conviction publicly searchable. Time spent incarcerated does not count toward the registration period, so the practical duration usually runs well past the nominal 15 or 25 years.
Consequences Beyond the Sentence
The formal sentence is often not the worst part. Several collateral consequences reach further and last longer.
Immigration
For non-citizens, a conviction can trigger removal or make someone inadmissible to the United States. The State Department’s Foreign Affairs Manual classifies a range of sexual offenses, including lewdness, gross indecency, and rape, as “crimes involving moral turpitude.”6Department of State Foreign Affairs Manual (FAM). Ineligibility Based on Criminal Activity – INA 212(A)(2) A conviction that lands in that category can bar entry or serve as grounds for removal, even for lawful permanent residents.
Expungement
Clearing a sex offense from your record is very difficult. Most states prohibit expungement or sealing for sex offenses outright, or impose waiting periods of 10 to 15 years with strict conditions. Some states carve out narrow exceptions for low-level misdemeanors, but felony sex offense convictions are almost universally excluded. If registration was required, the chance of ever clearing the record is close to zero in most jurisdictions.
Civil Commitment
Under the federal civil commitment program established by the Adam Walsh Act, a person in Bureau of Prisons custody can be civilly committed after their sentence ends if a court finds by clear and convincing evidence that the person has engaged in sexually violent conduct and suffers from a serious mental illness that makes it difficult to stop.7U.S. Sentencing Commission. Civil Commitment Program for Dangerous Sex Offenders Commitment lasts until the person is no longer deemed dangerous, which in practice can mean indefinitely. The conduct that supports commitment need not be the offense of conviction; it can include past behavior, including conduct while incarcerated.
Military Discharge
Service members convicted at court-martial face confinement, reduction in rank, forfeitures of pay, and separation. Enlisted members typically receive an Under Other Than Honorable Conditions discharge, and officers face dismissal. Either characterization sharply limits Department of Defense and Veterans Affairs benefits.
Employment, Housing, and Licensing
Background checks reveal these convictions, and registered offenders face additional public disclosure. Sex offense convictions are among the most disqualifying results in background screening, both for jobs and for rental applications. Professional licensing boards in healthcare, education, and law routinely deny or revoke licenses on that basis.
Defenses Worth Raising
The right defense depends on the specific charge and the wording of the state’s statute. A few come up repeatedly.
Constitutional Challenges
If the prosecution relies on an outdated or broadly worded statute, the law itself can be attacked. The vagueness doctrine, rooted in the Fifth and Fourteenth Amendments, holds that a criminal law cannot be so unclear that an ordinary person would not know what it prohibits. Overbreadth is the related challenge: a statute that sweeps in constitutionally protected conduct alongside genuinely criminal behavior can be struck down. Many sodomy laws fell this way even before Lawrence.
Consent and Privacy
Where the conduct at issue is between adults, consent is the strongest defense available. Lawrence protects private, consensual sexual conduct between adults, and if all parties were consenting adults acting in private, the prosecution usually cannot proceed.1Justia Law. Lawrence v. Texas, 539 U.S. 558 (2003) This defense does not reach acts involving minors, animals, coercion, or public conduct. It also does not help in bestiality cases, since animals cannot consent.
Entrapment
If police induced someone to commit an act they would not otherwise have committed, entrapment may apply. It takes more than showing that an undercover officer created an opportunity. The defendant must show government inducement, meaning persuasion, pressure, or extraordinary promises capable of overcoming a law-abiding person’s resistance, and that the defendant was not already predisposed to commit the offense.8United States Department of Justice Archives. 645. Entrapment – Elements Ready acceptance of the opportunity defeats the defense.
Insufficient Evidence
The prosecution must prove every element beyond a reasonable doubt. Challenging physical evidence, witness credibility, or identification is often the most practical route, particularly in cases that rest on a single witness or circumstantial proof.
The Cost of Defending a Charge
Felony sex offense cases are among the most expensive criminal matters to defend. Attorney fees commonly range from $5,000 to well over $100,000, depending on complexity, jurisdiction, and whether the case goes to trial. Expert witnesses, forensic evidence, and extended litigation push costs to the high end. A defendant who cannot afford counsel has the right to a court-appointed attorney, but the financial pressure of a sex offense prosecution reaches beyond legal fees. Lost employment, unstable housing, and the ongoing cost of registration compliance can follow for decades after the case ends.