Crime Against Nature in Louisiana: Penalties and Defenses

The crime against nature law in Louisiana, codified at Revised Statutes 14:89, criminalizes two things: certain sexual acts between people, and sexual relations or marriage between close family members. A basic conviction carries up to five years in prison and a $2,000 fine, but penalties climb steeply when a minor is involved, when force is used, or when the family relationship is close. One important caveat sits on top of all of it. The U.S. Supreme Court’s 2003 decision in Lawrence v. Texas blocks prosecution of consenting adults for private sexual conduct, so part of the statute is effectively dead letter even though Louisiana has never removed the language.

What the Statute Actually Prohibits

RS 14:89 has two distinct parts. The first covers what the statute calls “unnatural carnal copulation” between humans, whether same-sex or opposite-sex. Penetration is not required; the involvement of a genital organ of either person is enough for the conduct to fall within the statute. The law carves out one specific exception: anal intercourse is not charged as crime against nature when the circumstances would make it rape, forcible rape, or simple rape under Louisiana’s sexual assault statutes. In those cases, prosecutors charge the rape offense instead.¹

The second part is Louisiana’s incest provision. It criminalizes marriage to, or sexual intercourse with, a direct ancestor or descendant, a sibling, an uncle or niece, or an aunt or nephew, when the person knows the relationship exists. Knowledge of the family tie is an element the prosecution must prove.¹

One boundary worth flagging. Before 2018, RS 14:89 also covered sexual acts between humans and animals. Act 485 of the 2018 Legislative Session moved that conduct into a separate statute, RS 14:89.3. Convictions and registration obligations that predate the change remain in force.¹

Why Part of the Law Can’t Be Enforced

In Lawrence v. Texas, the U.S. Supreme Court held that consenting adults have a constitutional right to private sexual conduct, protected by the Due Process Clause of the Fourteenth Amendment. The decision struck down state sodomy laws across the country.²

The practical effect on Louisiana is that any prosecution of two consenting adults for private sexual conduct under RS 14:89(A)(1) would be unconstitutional. The language stayed in the code anyway. That gap between what the statute says and what the Constitution allows creates real risk of arrest even where a conviction cannot stand.

What Lawrence does not touch is just as important. Non-consensual conduct, acts involving minors, and incest fall outside the protected zone. Those parts of RS 14:89 are fully enforceable.³

Penalties Under RS 14:89

The base penalty for the “unnatural carnal copulation” provision between adults is a fine of up to $2,000, imprisonment with or without hard labor for up to five years, or both.¹

When the Victim Is a Minor

The numbers change dramatically once a minor is involved:

Victim under 18: fine up to $50,000, imprisonment at hard labor for 15 to 50 years, or both.
Victim under 14: fine up to $75,000, imprisonment at hard labor for 25 to 50 years, or both.

These minimums are mandatory. A judge cannot go below 15 years when the victim is under 18, or below 25 years when the victim is under 14.⁴

Incest Penalties

The incest tier depends on how close the family relationship is:

Parent-child, grandparent-grandchild, or sibling: imprisonment at hard labor for up to 15 years. No fine option.
Uncle-niece or aunt-nephew: fine up to $1,000, imprisonment with or without hard labor for up to five years, or both.

Closer blood ties bring harsher exposure and remove the option of a fine in place of prison time.¹

Aggravated Crime Against Nature

A separate and far more serious charge lives in RS 14:89.1: aggravated crime against nature. It applies in two situations.

The first is when the conduct involves force, coercion, or a victim who cannot consent. That covers any of the following:

The victim resisted and was overcome by force.
The victim was prevented from resisting by threats of serious, immediate bodily harm.
The offender was armed with a dangerous weapon.
The victim had an intellectual or mental disability making consent impossible, and the offender knew or should have known.
The victim was incapacitated by a narcotic or similar substance, and the offender was aware of the condition.
The victim was under 17 and the offender was at least three years older.

The second is familial sexual abuse of anyone under 18. It reaches a wide set of relatives, biological, step, and adoptive, including parents, grandparents, siblings, half-siblings, uncles, aunts, nephews, and nieces. Consent is not a defense.⁵

What Aggravated Charges Carry

Force, threats, or incapacity: imprisonment at hard labor for 3 to 15 years, with no probation, parole, or suspended sentence.
Familial sexual abuse of a minor: fine up to $50,000, imprisonment with or without hard labor for 5 to 20 years, or both.
Familial sexual abuse where the victim is under 13 and the offender is 17 or older: imprisonment at hard labor for 25 to 99 years, with at least 25 years served before parole eligibility, followed by lifetime electronic monitoring after release.⁵

The top tier functions as a life sentence in practical terms for most defendants.

Sex Offender Registration and Job Restrictions

A conviction under RS 14:89 can trigger sex offender registration, and the statute preserves all registration obligations tied to a crime against nature conviction, including those from before the 2018 amendments.¹

For anyone ordered to register on or after August 15, 2010, RS 15:553 imposes specific employment bans. A registered sex offender cannot:

Drive a bus, taxi, or limousine for hire.
Work as an in-home service provider entering residences.
Work as a door-to-door salesperson or solicitor of any kind.
Operate carnival or amusement rides, if the underlying offense involved a child.

Violating these restrictions is itself a serious offense: a fine of up to $10,000 and five to ten years at hard labor, with three years served before parole eligibility.⁶

Registration also brings housing limits, community notification, and professional licensing barriers in many fields. Those consequences often outlast the prison sentence.

Defenses to a Crime Against Nature Charge

Which defense fits depends on what part of the statute is being charged.

For a prosecution based on consensual conduct between adults, the defense is constitutional. Lawrence v. Texas forecloses the case, and a motion to dismiss on Fourteenth Amendment due process grounds is the standard response.²

For charges that remain enforceable, minors, force, or incest, the defense turns on evidence. These cases often play out in private settings, so the prosecution frequently leans on testimony and circumstantial proof. Defense strategy commonly targets how evidence was collected, the reliability of witness statements, and, in incest cases, whether the state can prove the defendant knew the family relationship existed.

In aggravated cases built on incapacity, the defense may challenge whether the victim was truly unable to consent or whether the defendant reasonably knew about the condition. For age-gap charges involving a minor, be aware that Louisiana law generally does not allow a mistake-of-age defense once the ages are established.

1
Louisiana State Legislature. Louisiana Code RS 14:89 – Crime Against Nature
2
Justia. Lawrence v. Texas, 539 US 558 (2003)
3
Legal Information Institute. Lawrence v. Texas
4
FindLaw. Louisiana Revised Statutes Title 14 Section 89 – Crime Against Nature
5
Louisiana State Legislature. Louisiana Code RS 14:89.1 – Aggravated Crime Against Nature
6
Justia Law. Louisiana Revised Statutes Title 15 RS 15:553 – Prohibition of Employment for Certain Sex Offenders