Is Incest a Crime?

In the United States, every state has one or more laws banning incest through criminal law, marriage prohibitions, or both. While states vary in defining the boundaries of prohibited intrafamilial relationships and the exact behaviors that are off-limits, the underlying goals and policy considerations of incest laws remain fairly consistent among states.

This article will review criminal laws that prohibit and penalize incest under state law.

What Is Incest? Is Incest Legal?

Incest refers to sexual and marital relations between closely related family members. For the most part, state incest laws prohibit marriage and sexual intercourse between close blood relations. Many states also include step, foster, and adoptive relations. In some states, even unconsummated marriage between individuals related to a certain degree will be considered incest.

What Is Considered a Close Familial Relationship?

For the purposes of incest laws, "family" can mean several things: blood relations (whole or half), family by adoption or marriage (including stepfamily members), foster families, and sometimes even "family-like" situations (such as a parent and child who lives with the parent's significant other).

Nearly all states prohibit sexual intercourse between close blood relations—parents and children, siblings, grandparents and grandchildren, and aunts or uncles and their nieces or nephews. Most incest laws also pull closely-related cousins within their scope. Typically, the more distant the relation, the less likely that it will be considered a prohibited relationship for purposes of incest law.

Some states' laws list the specific family relationships (like siblings) that are prohibited. Others might indicate prohibited relationships by degree, such as any blood or marital relation closer than the third degree. Quite a few states tie their criminal laws on incest to their marriage laws. So, if the law prohibits marriage between persons related by blood, criminal incest laws make sexual conduct in those relationships illegal, as well.

What Conduct Is Prohibited Under Incest Laws?

Another difference among state incest laws concerns the type of conduct prohibited. Some states' incest laws prohibit only sexual intercourse or penetration, while others make any sexual conduct illegal in incestuous relationships. A state's criminal laws might also make marriage between close relations a crime even if no sexual relations have occurred. Some states only criminalize incest committed by or between adults.

Why Is Incest a Crime?

Society generally condemns incestuous relationships, finding them repulsive and unnatural. These relationships are often associated with child sex abuse, even though that's not the behavior addressed by incest laws.

Some commonly cited reasons for making incest a crime include:

• preventing genetic disorders in offspring
• promoting family security and unity
• protecting children from sexual abuse
• preserving public morals, and
• preventing unnatural and immoral conduct.

These perceptions are so strong that prevailing views on privacy rights and the right to marry are often overlooked in incest cases. Scientific research even suggests that concerns regarding genetic disorders don't necessarily support the rationale given for incest laws.

What Are the Penalties for Incest? Is Incest a Felony?

Criminal penalties for incest vary by state, but nearly all states provide felony penalties for incest. Felony penalties can range anywhere from a year or more and up to life in prison. There's no standard penalty for incest—they range anywhere from a few years in prison to the possibility of decades behind bars.

Incest Crimes and Penalties

Some states have one penalty for all incest crimes, but quite a few have varying degrees and penalties for incest. For instance, a number of states increase incest penalties when one of the parties is a child. This offense might be considered aggravated incest or incest with a minor. A few states place incest crimes involving a child under their sexual abuse or criminal sexual conduct laws. States may also have different penalties based on the type of conduct involved (sexual intercourse vs. contact), the relation between the parties (blood relation vs. adopted or by marriage), or a combination of any of these.

Examples of State Criminal Penalties for Incest

Because the penalties for incest are so wide ranging, we can't list them all. Here are some examples based on the descriptions listed above.

One penalty. Florida and Oregon are examples of states that have one incest penalty. Florida makes incest a felony of the third degree, and Oregon classifies it as a class C felony.

Age of victim. Colorado and Georgia are two states that base their incest penalties primarily on the age of the victim. Stiffer penalties apply when in Colorado when one party is younger than 21 and in Georgia when one party is younger than 14.

Familial relation. Louisiana and Texas impose penalties based on how close the parties are in relation. For instance, Louisiana makes incest between parent and child a 15-year felony, whereas between an uncle and niece, it's a 5-year felony.

Sexual conduct. In Michigan, the felony penalty depends, in part, on the conduct involved. Harsher penalties apply in cases of sexual penetration versus sexual contact.

(Colo. Rev. Stat. §§ 18-6-301, -302; Fla. Stat. § 826.04; Ga. Code § 16-6-22; La. Rev. Stat. § 14:89; Mich. Comp. Laws §§ 750.520B, .520C; Or. Rev. Stat. § 163.525; Tex. Penal Code § 25.02 (2024).)

Prosecution of Incest Crimes

When it comes to prosecuting incest crimes, several issues commonly arise, including who will be prosecuted, what the prosecution must prove, and what other charges might apply.

Who Is Charged in Incest Cases?

In some incest cases, both parties have committed a crime and the prosecutor can file criminal charges against both individuals. However, where one party is a minor and the other an adult, usually the adult will face criminal charges and the minor considered a victim. Several states only place criminal liability on adults who knowingly enter these relationships, not children.

Knowledge of Relationship by Blood or Marriage

To secure a conviction for incest, a prosecutor typically needs to prove that the defendant knew they were related by blood or marriage. If the parties had no idea they were second cousins, their marriage might be voided (assuming they married) under the law, but they couldn't be found guilty of incest in most states.

Other Possible Criminal Charges

Sometimes, a situation involving incest implicates other criminal laws. For example, depending on the circumstances, sexual conduct between the parties might constitute child abuse, rape, or statutory rape. Local prosecutors sometimes have discretion about whether to bring charges under the state incest law or other applicable laws.

Defending Against Incest Charges

A person facing criminal charges for incest could raise one of several defenses. One strategy is to poke holes in the prosecution's cases. A defense attorney might argue that the prosecutor failed to prove the required degree of familial relation or that the defendant knew of the familial relationship. Another option would be to challenge the constitutionality of the statute as a violation of the right to marry or the right to privacy. Consent, though, is not a defense in incest cases. Incest laws target the relationship, not the act.

Talk to a Lawyer

If you're facing an incest charge, consider consulting with an experienced criminal defense attorney who regularly practices in your area. A lawyer can evaluate the strength of the prosecution's case against you, help develop any defenses that might apply to your case, and knows how local prosecutors and judges typically handle cases like yours.