Since coital incest occurs chiefly before marriage, we shall treat it in this chapter. Coital incest is defined as coitus had by a postpubertal male with a female whom he could not marry because of her familial
relationship (genetic or social) to him. All persons interviewed were asked concerning incestuous coitus; unfortunately, we did not inquire about petting without coitus. Under incest we have included coitus between first cousins, since most states prohibit first-cousin marriages. We have departed from the above definition by considering as incest coitus with a sister-in-law, an act which most individuals regard as close to, if not actually, incest, despite the fact that one can marry an ex-sister-in-law. It is curious that despite Biblical exhortations, marrying a former sister-in-law is often frowned upon—particularly if divorce rather than death made the marriage possible.
Incestuous behavior is commonest with first cousins and least common with mothers. The sequence is: first cousin, sister, aunt, sister-in-law, then (almost equal), niece and daughter, and lastly, mother. Note the commonest four relatives are those apt to be near the subject’s age; an aunt who is one’s peer is not uncommon, particularly in the lower socioeconomic stratum. The frequency of sister incest may be explained by the combination of proximity and very early coitus; brother-sister incest is almost invariably at a young age and seems essentially a carry-over from prepubertal sex play. Incest with grandmother and granddaughter has been omitted from the list above because almost no cases of coitus exist in our sample.
Aside from the obvious statement that coital incest, as defined above, is most prevalent among the incest offenders vs. adults and minors, little can be said. Due primarily to the ages of their daughters or stepdaughters, coital incest is uncommon among the incest offenders vs. children. The reader will recall that coitus is not a requisite in the definition of incest offenders. Except for first-cousin incest, incest is such a minority phenomenon that any generalizations are reduced to the status of near speculation. Nevertheless, it is clear that the prison group and the sex offenders as a whole far exceed the control group in incestuous behavior. Lastly, the heterosexual aggressors appear to be the most incest-prone of any group except for the incest offenders. All three aggressor groups have over one eighth of their members with incestuous coitus, and consequently occupy die upper portion of the rank-order.
*301\161\2*
