Incest Laws in the United States

Incest is defined as sexual activity between close family members. It is looked down upon and forbidden in a large majority of cultures. In most Western societies, incest is illegal and punishable by law. There is some evidence that incest was controversial in ancient times, practiced by the Egyptians but frowned upon by the Romans. Incest sometimes appeared in royal dynasties, in order to keep wealth and political power within the royal families. Although there is some evidence of incest occurring in the past, it was by probably not too common. Incestuous marriages did occur, but they certainly were rare (Wikipedia, 2006).


Looking at the statistics today, it seems that incest is more common than people may believe. It is estimated that one in three girls and one in six boys are sexually abused before the age of 18. Of sexually abused girls, over half are abused by their biological fathers. Uncles and stepfathers are the other leading offenders. Incest is sexual relations between two people who are so closely related that marriage is illegal or forbidden by custom.  The participants could be blood relatives or relatives through marriage. This definition excludes husband and wife relatives. One of the persons often involved in an incestuous relationship is a child. Although adult and sibling incest can occur, incest is more likely to take place between an older and younger relative. The most commonly reported incestuous relationship is between a father and his daughter. However, studies show brother-sister and first-cousin sexual activity occur more often. Studies have also shown that in most sibling or cousin incest situations, one or both parents seem to be absent emotionally or physically. According to the National Center for Victims of Crime, most cases of rape in the United States reported are within a family. Ninety nine percent of sexual abusers are men, and many of these men were themselves abused as children. Although most sexual abuse victims are females, males account for at least a quarter of those abused (ICASA).



Incest is often though of as sexual assault of children and can be a form of rape in many cases (RAINN, 2006). However, incest can also be consensual. In some cases, incest can occur between two consenting adults who may enjoy the act and their relationship. This is not often the case though, and incest can result in long-term negative consequences.


Children who are victims of incest frequently experience the following:

  • withdrawal
  • depression
  • sleeping and eating disorders
  • anxiety
  • guilt
  • academic problems


Children and adults who are victims of incest may develop a fear of sex or other sexual disorders. They may have a difficult time trusting other people, especially if the offender was someone who was once trusted by and close to the victim (RAINN, 2006).


In the United States, incest is defined as sexual contact between those so closely related that if they were to marry it would be illegal. Expectations about incest differ from culture to culture, as most standards for sex do, so what is considered taboo in the US or other Western cultures may not be viewed negatively in other cultures. In some areas of the Arab world and India for example, about half of marriages occur between first cousins (RAINN, 2006). Since different cultures have different standards for many sexual matters, it is difficult to create a worldwide definition of incest and when it should be a crime. Incest, particularly non-consensual, can frequently result in long lasting negative psychological consequences.



1. Illinois Coalition Against Sexual Assault. Adult Survivors of Childhood Sexual Abuse
2. Rape Abuse and Incest National Network. (2006). Incest.
3. Wikpedia. (2006). Incest.


Last Updated: May 25, 2012


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