1. Background
   1. Problem of Definitions
   2. Evidence and Standard of Proof
2. The Evidence
   1. Changes in Rape Rates
   2. Correlational Evidence
      1. Danish and Other Cross-Cultural Data
      2. Sex-Magazine Circulation
      3. Sex Offenders and Pornography
      4. Conclusions from Correlational Evidence
   3. Experimental and Clinical Evidence
      1. Arousal
      2. Effects on Attitudes Toward Rape- "Disinhibition"
      3. Overall Evidence for "Causation"
   4. Evidence Against Causation
3. Conclusion
4. Notes

Experimental and Clinical Evidence

A "casual" connection between circulation of adult material and sexual violence may only be inferred if one or more plausible explanations exist for how such "causation" could exist. Experimental evidence is particularly important in testing the likelihood of such causal links; as noted above, however, ethical and practical constraints insure that such evidence will always be open to charges of artificiality and obliqueness.^[30] Simply put, actual rapes cannot be staged in the laboratory, nor can known rapists be subjected to testing which might provoke future violence. Retrospective "clinical" evidence, although it does generally relate to "real" rapes by "real" offenders, has the even more crippling handicap of relying on faulty, and self-serving, memory. Yet experimental and clinical evidence remain in this area the most effective tools for testing the "validity" of correlational data.

Searching the evidence for suggestions of a "cause-and-effect" pornography/rape connection inevitably leads down two different paths. The first observes the capacity of pornography to effect arousal in the viewer, and examines whether such arousal can be causally linked to sexual violence. The second, somewhat more indirect approach examines the effects of pornography consumption on viewer's attitudes, then considers whether such changes in attitudes could plausibly affect the incidence of rape.

Arousal

One of the few undisputed properties of sexually explicit materials is their capacity to cause sexual arousal in many, if not most viewers.^[31] One strand of experimental research has attempted to determine whether this arousal, alone or in combination with other factors, increases or decreases aggressive behavior in laboratory settings.

With regard to "normal" subjects (usually college-age male volunteers), the results have been mixed, or at least highly complex. Thus highly arousing erotic materials, when combined with prior or subsequent anger, seem clearly to provoke heightened aggression by males against males.^[32] But in a recent review of the research Professor Donnerstein made the following, more limited, statement about the effects of exposure to nonviolent pornography on male aggression toward women:

... The question of whether or not nonaggressive pornography has an influence on aggression against women is not simple to answer. For one thing, there is not that much experimental research on the topic. Also, studies investigating this issue have differed in many ways.... These studies indicate that under certain conditions exposure to pornography can increase subsequent aggression against women. What seems to be required, however, is a lowering of aggressive inhibitions. This change in aggressive predisposition can come about in a number of ways. First, a higher level of anger, or frustration, than that exhibited in a laboratory setting could influence the effects of pornography on aggression against women. There is no question that such levels are present in the real world. Second, as mentioned earlier, drugs, alcohol, and other aggression disinhibitors very likely increase aggressive response to pornography. The main mediating factor, however appears to be the type of material viewed prior to an aggressive opportunity.^[33]

While experimental findings are neither conclusive nor absolutely consistent, the bulk of research to date supports the conclusion: that where highly arousing nonviolent pornography is viewed in a context of anger or provocation, aggressive behavior against women increases. Outside the context of provocation, in Professor Donnerstein's view, nonviolent material which is "either mildly arousing or leads to a positive affective reaction" does not appear to increase subsequent aggressive behavior, while that which depicts "unequal power relationships with women" or "women as sexual objects" may provoke such behavior. As part of his belief that the issue warrants "much more investigation" he notes that the effects of nonaggressive pornography may not occur with only a single exposure,^[34] which would explain varying results in experiments based on single exposure. Growing habituation to standard "pornography" over the years among likely experimental subjects may substantially affect the results of research.^[35]

Along slightly different lines, a certain amount of experimental and clinical evidence suggests that rapists are aroused by nonviolent, sexually explicit materials, and that some consciously use such materials to prepare for and execute sexual violence. Thus rapists are normally as strongly aroused to consensual nonviolent pornography as nonrapists; they are, moreover, at least as aroused to images of mutually consenting sex as they are to those of rape.^[36] Does this arousal to mutually-consenting imagery cause some of them to commit sex crimes which they might otherwise avoid? Evidence from at least Dr. William Marshall suggests that the answer may be yes: 33 percent of rapists interviewed for his study "had at least occasionally been incited to commit an offense by exposure to one or the other type of pornography specified in this study."^[37] Of that group 75 percent reported that they had at least occasionally used 'consenting' pornography to elicit rape fantasies which in turn led to the commission of a rape (or an attempt at commiting a rape)."^[38] A large number of other rapists in his sample used "consenting pornography" to "evoke rape fantasies" and consequent arousal. Indeed, fully 52 percent of the rapists in his sample (as compared to none of the "normals") used pornography "always" or "usually" during masturbation.^[39]

Dr. Abel, while stating the belief that direct incitement to rape can be traced to sexually explicit depictions only in "exceedingly rare" cases, also found that a very high proportion of rapists use consenting "erotica" to elicit and maintain deviant arousal. Recent research has shown a high correlation between sexually deviant fantasies and deviant behavior,^[40] and many treatment programs for rapists have been predicated on altering their deviant behavior through changing their fantasies and arousal patterns.^[41] Dr. Abel and his colleagues at one point called for recognition of "fantasy as the pivotal process leading to deviant behavior."^[42] To the extent that nonviolent, "consensual" pornography contributes to provoke or maintain deviant fantasy and arousal in rapists, it may be considered a "cause" of their deviant behavior.

Turning back to the general population-that is, both sex offenders and "normals"-it is important to note two significant theories concerning sexually aggressive behavior which are predicated on the biological forces of simple arousal. The first, called the "general emotional arousal theory," is described in one study as predicting that "by arousing either the sexual or aggressive drives in an individual, the overall general level of arousal would be increased, thereby making both sexual and aggressive responses more probable"^[43] The second theory, which is more subtle and more flattering to the human will, adds an additional cognitive layer to the general-arousal theory:

While evolutionary forces may have provided a biological basis for a link between sex and aggression, it is our contention that learning variables may accentuate or attenuate this relationship. We hypothesize that in human beings the biological link plays a relatively minor role and that to a large extent the relationship between sexual arousal and aggression is mediated by learned inhibitory and disinhibitory cues.^[44]

Both theories associate arousal with aggression; the second merely adds the additional mediating factor of "learned inhibitory and disinhibitory cues." If this association is ultimately found valid, then a "casual" connection between circulation of highly arousing sexually explicit materials and the incidence of rape would be both clear and easy to explain: more sexual arousal in society (as a consequence of pornography) inevitably produces more sexual and more aggressive behavior, both of helpful and harmful varieties. If viewing sexually explicit materials cause Americans to have more sex, then some of that incremental sexual behavior will be of a sexually aggressive nature. The "rate" of rape as a percentage of all sexual intercourse will not change,^[45] but the absolute number of rapes, and the number of people victimized by rape, will increase.^[46]

The ability of sexually explicit materials to arouse those who view them may, therefore, be in itself a "cause" of sexually aggressive behavior-perhaps simply for rapists, or perhaps in a more general way. This evidence does not distinguish sexual material as being more culpable than, say, alcohol as a causal factor in rape-but it does suggest that the more highly arousing the material is, the greater will be its ultimate effect. Thus highly explicit sexual material will likely have more of an impact than material which is less sexually arousing. The evidence does not indicate, moreover, that "learned" cultural mores and social attitudes have no effect on preventing rape; rather, those factors may play a significant role in mediating the negative biological forces that push men toward rape.

If arousal to rape is mediated by learned attitudes, however, a change in those attitudes may in itself change the likelihood of rape occurring-may become a "cause" of sexual violence.^[47]

Thus it is crucial to consider what the available experimental evidence shows about the effects of viewing nonviolent sexually explicit materials on attitudes toward women and toward rape. Although Professor Neil Malamuth and others have examined in some depth that question with regard to sexually violent materials, only very recently has substantial evidence emerged about materials which are similar to much of what is contained in the "adult magazines" examined by Baron and Strauss.

Despite some surface tension in the results, that evidence strongly suggests that such materials, when viewed in substantial quantities over extended periods of time, tend to increase callousness toward women and acceptance of "rape myths". Thus six hours of viewing "commonly available (nonviolent)pornography" over a six-week period caused men in several experiments to become more accepting of "gender dominance"^[48] and "sex callousness"-to trivialize rape, and to discount the trauma suffered by its victims.^[49] The careful and extensive study by Professor James Check found repeated exposure to the "most prevalent" form of nonviolent pornography currently available-that depicting the women subjects in a "dehumanized fashion"-had even stronger effects on subjects' "reported likelihood of rape" and "reported likelihood of forced sex acts," than sexually violent materials.^[50] Both types of material had particularly profound effects, it is important to note, on those subjects with higher tendencies toward psychoticism.^[51] Exposure to "nonviolent erotica"-described as being the type of depiction used in sex education and therapy materials-was found to have at best an ambivalent effect: likelihood-to-rape scores increased among those viewers to a level where they were not significantly different from either those in the "no exposure" or the "dehumanizing pornography" groups.^[52]

Only one study currently extant seems to cast doubt on the tendency of viewing nonviolent pornography to increase "rape myth acceptance:" In a recent doctoral dissertation Daniel Linz found that exposure of university psychology students to either two or five full-length X-rated nonviolent films over, respectively, a three- or ten-day period did not affect their attitudes toward a rapist or his victim in a simulated rape trial shown two days after exposure was completed.^[53] Such attitudes were dramatically affected, by contrast, in a comparison group observing four extremely violent R-rated films with far less sexual content. Unfortunately, Linz' study is not directly comparable with previous ones in this area. First, Linz limited the time frame of exposure to less than two weeks.^[54] Second, his study did not measure the subjects' scores on "likelihood-to-rape" or "likelihood-of-forced-sex-acts" scales similar to those used by Professor Check but rather studied subjects' reactions to a simulated rape trial. Reaction to the plight of a specific rape victim in a simulation is not as direct-and so at least arguably not as useful-a measure as answers to questions about what the subject himself desires to do. Because his study did not include, as did Check's, comparisons based on his subjects' prior viewing habits, Linz' results must be treated with extreme caution. It is possible that the strong reaction to R-rated violent films was simply a function of low prior exposure to those films-the films may have their effects because of "shock value."^[55] (College-age participants in studies of this nature are known, by contrast, to have previously seen large quantities of "commercialized erotica" and so would not likely have been as jarred by seeing more of it.)^[56] The study did not measure the effects of X-rated violent films, which would have served to indicate the role of sexual explicitness in mediating the effects of viewing violence.

Despite its methodological limitations, the Linz dissertation does contribute one highly important finding to the data on nonviolent material. In a follow-up study of the participants in his experiment Linz conducted careful "debriefing" of all subjects with regard to the specific material each had seen, then measured their attitudes toward rape after a six-month period. For those subjects who had seen, then been "debriefed" regarding R-rated violent and R-rated nonviolent materials, a dramatic reduction in "rape myth acceptance" occurred-with virtually no difference between those two groups in their final scores. "Debriefing" was thus seen as a success for both groups. Subjects who had seen X-rated nonviolent materials, by contrast, showed only the most minimal decline in "rape myth acceptance" after "debriefing" the lapse of six months-so that at the point of follow-up measurement they showed substantially higher toleration of rape than either of the R-rated groups.^[57] The significance of this finding, not recognized by Linz himself, is its tendency to show long-term effects of "X-rated" material even in the face of positive efforts to "educate" viewers. In the "real world", as opposed to the laboratory, viewers of sexually explicit materials normally receive messages-" inhibitory cues"-contradicting those in the materials they watch. The Linz study provides tentative evidence that for sexual materials with a high degree of explicitness, such real-life "debriefing" may be unsuccessful.

The overall results of work on "long-term" exposure to standard, nonviolent pornography was confirmed and summarized in a statement by Professor Donnerstein in 1983:

Let me end up talking in the last couple of minutes, about the long term research. Researchers like myself and Neil Malamuth at UCLA are looking at massive long term exposure to this material. Some interesting things occur. If you expose male subjects to six weeks' worth of standard hard-core pornography which does not contain overtly physical violence in it, you find changes in attitudes toward women. They become more calloused towards women. You find a trivialization towards rape which means after six weeks of exposure, male subjects are less likely to convict for a rape, less likely to give a harsh sentence to a rapist if in fact convicted.^[58]

Professor Donnerstein went on to say:

In our own research we are looking at the same thing. Let me point out one thing. We use in our research very normal people. I keep stressing that because it is very, very important. What we are doing is exposing hundreds and hundreds of males and now females to a six-week diet of sexually violent films, R-rated or X-rated or explicit X-rated films. We preselect these people on a number of tests to make sure they are not hostile, anxious or psychotic.

Let me point out the National Institute of Mental Health and the National Science Foundation and our own subjects committee will not allow us to take hostile males and expose them to this type of material because of the risk to the community. They obviously know something some of us do not.^[59]

Although Professor Donnerstein himself has recently emphasized most the harmful effects of violent depictions, the research strongly seems to support the proposition that longer-term, substantial exposure to "standard" nonviolent, sexually explicit materials acts as a "disinhibiting cue" for rape.

No experiment has, for the reasons suggested by Professor Donnerstein, tested the effects of nonviolent, sexually explicit material on the aggressive behavior of known sex offenders or, indeed, those with even a tendency toward psychoticism. Experiments with "normal" subjects, however, have suggested two separate, but quite possibly interdependent means by which such material could heighten the probability of sexual violence. The simple capacity of nonviolent material to produce strong arousal in both offenders and the general population may in and of itself produce higher levels of sexual violence. Of equal importance, "standard" commercial pornography may over time and with significant exposure work to undermine "learned" inhibitions against sexual violence. While "adult men's magazines" have not been the normal focus of experimental investigation, the material they contain is sufficiently arousing, and sufficiently tied to views of women only as "sexual objects;" as to make the reasonable inference that these findings are applicable to them as a class. Thus the Badgley Committee in Canada found that in a group of "adult" magazines essentially the same as those studied by Baron and Strauss, photographic depictions of sexual bondage were three times as frequent as oral-genital contact, five times as frequent as vaginal penetration with penis or finger, and ten percent more frequent even than any form of kissing.^[60] While further research is clearly indicated to determine the effects of this extremely common material, at present it may fairly be seen as falling within the range of materials as to which current experimental and clinical evidence is highly relevant.^[61]

Statement of Father Bruce Ritter