The 1986 Final Report of the Attorney General's Commission on Pornography examined five different classes of material: (1) sexually violent material; (2) nonviolent materials depicting degradation, domination, subordination, or humiliation; (3) non-violent and non-degrading materials; (4) nudity; and (5) child pornography. The first two categories demonstrated negative effects on behavior, the third showed mixed results, the fourth was not found harmful but the commissioners agreed it was morally objectionable, and the fifth involved sexual exploitation and was already outlawed.

Let us briefly look at the psychological effects of pornography. Psychologist Edward Donnerstein (University of Wisconsin) found that brief exposure to violent forms of pornography can lead to anti-social attitudes and behavior. Male viewers tend to be more aggressive toward women, less responsive to the pain and suffering of rape victims, and more willing to accept various myths about rape.

Dr. Dolf Zillman and Dr. Jennings Bryant showed that continued exposure to pornography had serious adverse effects on beliefs about sexuality in general and on attitudes toward women in particular. They also found that pornography desensitizes people to rape as a criminal offense and that massive exposure to pornography encourages a desire for increasingly deviant materials that depict violence (such as sadomasochism and rape).

Feminist author Diana Russell notes in her book Rape and Marriage the correlation between deviant behavior (including abuse) and pornography. She also found that pornography leads men and women to experience conflict, suffering, and sexual dissatisfaction.

Statistical studies by sociologists Murray Straus and Larry Baron (University of New Hampshire) found that rape rates are highest in states that have high sales of sex magazines and lax enforcement of pornography laws.

Michigan state police detective Darrell Pope found that in 41 percent of the 38,000 sexual assault cases in Michigan between 1956 and 1979, pornographic material was viewed just prior to or during the crime. This finding corroborates research done by psychotherapist David Scott, who found that "half the rapists studied used pornography to arouse themselves immediately prior to seeking out a victim."

Edward Donnerstein and Daniel Linz, writing in Psychology Today, report that "in one study by Malamuth . . . men read several stories, some of which were about a woman being raped. When the men were asked how likely they would be to behave as the rapists did if they knew they would not be caught, more than half indicated some likelihood of behaving that way."

Some psychologists, however, do not believe that pornography contributes to rape. They believe that men may be "generally callous about rape to begin with." But if there are people in our society already predisposed toward rape, will not pornography fuel that desire and increase the possibility that they will begin to act out their fantasies?