Free US Law Dictionary

Incest

Incest is sexual activity between closely related persons (often within the immediate family) that is illegal or socially taboo. The type of sexual activity and the nature of the relationship between persons that constitutes a breach of law or social taboo vary with culture and jurisdiction.

Most incest cases reported in scientific studies are between adults and prepubescent or adolescent children, and particularly between fathers or other male relatives, and girls. This is a form of child sexual abuse[1] that has been shown to be one of the most extreme forms of childhood trauma, a trauma that often does serious and long-term psychological damage, especially in the case of parental incest.[2]

Adults who were incestuously victimized by adults in their childhood often suffer from low self-esteem, difficulties in interpersonal relationships, and sexual dysfunction, and are at an extremely high risk of many mental disorders, including depression, anxiety, phobic avoidance reactions, somatoform disorder, substance abuse, borderline personality disorder, and complex post-traumatic stress disorder.[2][3][4]

Consensual mutually desired adult incest is very rare, found almost exclusively between kin who were separated early in life and therefore did not experience early association and the related development of the natural adaptation for incest avoidance.[1] Consensual incest between adults is criminalized in most countries, although it is seen by some as a victimless crime.[5]

Incest is sexual activity between family members of either sex and age, with or without consent (depending on local laws, especially age of consent). However, which family members constitute those covered by the incest prohibition is determined by the society in which the persons live. Some societies consider it to include only those who live in the same household, or who belong to the same clan or lineage; other societies consider it to include "blood relatives"; other societies further include those related by adoption or marriage.[6]

Most societies have some form of incest avoidance.[7][8] The incest taboo is and has been one of the commonest of all cultural taboos, both in current nations and many past societies,[9] with legal penalties imposed in some jurisdictions. Most modern societies have legal or social restrictions on closely consanguineous marriages.[10] However, in some societies, such as that of Ancient Egypt, brother–sister, father–daughter, and mother–son relations were practiced among royalty.[11][12] In addition, the Balinese[13] and some Inuit tribes[14] have altogether different beliefs about what constitutes illegal and immoral incest.