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

Correlational Evidence

Our predecessors on the 1970 Commission had no sophisticated "correlational" data before them. Indeed, the only "correlational" data which they considered was of the sort discussed above-general trends in the sex-crime rates measured for time periods in which sexual materials were becoming more available. Unfortunately, for reasons discussed below, that sort of evidence is far too crude to be of significant value, and points, in any case, in no particular direction. Far superior correlational data has in the meantime come to the fore, and it shows that a statistical relationship does appear to exist between consumption of certain types of sexual materials and rape rates. Both types of data invite the most careful attention.

The 1970 Commission was impressed, as was the Williams Committee later, by studies on Denmark conducted by Berl Kutchinsky in which he found that relaxation of Danish pornography laws coincided with a decrease in reported sex crimes. Since that time Kutchinsky's work has been repeatedly criticized, and he himself has been forced to concede that, at least with regard to rape, liberalization of pornography laws was followed ultimately by increases in reports of rape to police.^[7] Further, Kutchinsky's approach fails to be even minimally persuasive for two crucial reasons. First, he does not account in any meaningful way for other social forces which might have affected Danish sex crime rates independently of pornography consumption. He fails to note, for example, that sex crime rates in Denmark might have been artificially high during the 20 years after the German occupation of World War II, a conflict described by one historian of Scandinavia as "shattering physically as well as emotionally."^[18] A drop in sex crimes during the late 1960's and after would thus be the result simply of recovery from social disintegration wrought by war. Second, and substantially related, Kutchinsky fails to consider the case of Norway-a country with a similar culture and a similar war experience-which has maintained far stricter laws against pornography,^[19] and has apparently enjoyed even greater success in combatting sex crimes.^[20] In the end Kutchinsky's analysis seems shallow and almost completely without value for analysis of the American experience and American policy.

A more appealing cross-cultural approach, but one with only marginally greater usefulness for our purposes, is that taken by Dr. John Court (1984). His research has examined the temporal changes in rape rates in a wide variety of countries in periods of greater or lesser legal control of pornography. His conclusion, presented with considerable cogency, is simply that greater legal control of pornography appears to hold down rape rates as well. Yet for all its resourcefulness Court's work fails, like that of Kutchinsky, to place the changes studied in careful historical and cultural perspective: thus Singapore, South Africa, Australia and Hawaii are all compared with little contextual information. An additional, related limitation on the helpfulness of his findings arises from his inability to show, like Kutchinsky, whether actual consumption patterns fit neatly into the patterns of changing legal regulation of sexually explicit materials. Our experience of American enforcement of obscenity laws indicates that such laws are often honored as much in the breach as in the observance.

Interesting as the work of Kutchinsky and Court is, we have had the benefit of receiving a body of correlational evidence of far greater power. The research of Baron and Strauss (1984, 1985) supplemented by others, has shown a strong statistical relationship between state-by-state circulation rates for the most widely read "men's magazines" and state-by-state reported-rape rates. That relationship persists even when every other factor theoretically associated with rape is controlled for: indeed, they found that the Sex Magazine Circulation Index has a consistently stronger statistical relationship with rape rates than any other factor tested." Further, in the model developed by Baron and Strauss other variables theoretically expected to be related to rape rates in fact met expectations: those factors (e.g., percent urban, percent poor) together with the Sex Magazine Circulation Index explain 83 percent of state-to-state variation in rape rates.^[22] Two independent studies, by Scott (1985) and Jaffee and Strauss (1986) have not only replicated the Baron and Strauss results for different years, but have cast doubt on potential "third factors" which would make the sex-magazine/rape association spurious. Baron and Strauss offered two such factors as possibilities: (1) a cultural pattern emphasizing "compulsive masculinity"; and (2) the degree of "sexual openness" within states. The first of those suggestions was undercut by Scott's finding that circulation of men's "outdoor magazines" is not associated with state-by-state rape rates. In addition, Baron and Strauss found that controlling for the "index of legitimate violence" and the general violent-crime rate-both seemingly plausible measures of a culture of "compulsive masculinity"-in no way lessened the sex-magazine/rape correlation. Nor did controlling for measures of the status of women-a plausible inverse measure of the degree of "compulsive masculinity" within a given state. Finally, the recent work of Check (1984) and Zillman and Bryant (1984, 1985) indicates that under experimental conditions, massive exposure to mainstream pornography may cause male viewers to become more callous and domineering in their attitudes toward women. Thus pornography may itself be a causal factor in creating a culture of "compulsive masculinity," and even if a correlation could be shown between such a culture and the incidence of rape, the association of the latter with sex-magazine circulation would still not be proved spurious.

As for the other "third factor" suggested-the degree of "sexual openness"-the recent study of Jaffee and Strauss (in press) measured the impact of the Sexual Liberalism Index on the Baron and Strauss formulae. While finding that sexual openness and tolerance is correlated, to a small but significant degree, with increases in reported rape rates, Jaffee and Strauss discovered the inclusion of the new index had no effect at all on the sex-magazine/rape association. While continuing to hold out hope-against all the evidence mentioned in the previous paragraph-that a relationship between "hypermasculine gender roles" and rape rates would render the sex-magazine correlation spurious, they felt compelled to conclude that their research "suggests that there may be more to the pornography-rape linkage than originally expected. That is, the type of material found in mass circulation sex-magazines may, as claimed by critics of such material, encourage or legitimate rape."^[23]

Somewhat less suggestive and useful, but nonetheless important, is correlational evidence exploring links between the use of sexually explicit material by sex offenders and their behavior. Dr. Gene Abel's (1985) study, in particular, is directly pertinent to the issues raised by Baron and Strauss: in treatment of 247 outpatient sex offenders (paraphiliacs), well over half admitted to use of adult men's magazines or similar material, and 56 percent of rapists stated that such materials "increased their deviant sexual interests." Comparison of those offenders who use "erotica" and those who do not produced only one statistically significant difference of direct relevance: users of "erotica" maintained their paraphilia far longer than nonusers. Between those whose deviant arousal was increased by "erotica" and those whose deviant arousal was not increased two statistically significant differences emerged: (1) the aroused-by-erotica subjects maintained their paraphilia longer; and (2) they had less "ability to control their behavior." On the whole, Dr. Abel concluded that "erotica ... does not appear to affect significantly the behavior of sex offenders."^[24]

Careful review of Dr. Abel's results and of his oral testimony, however, tends significantly to undercut that assertion. To begin with, the mean number of sex crimes committed by users of erotica was 29 percent higher than the mean for nonusers. Dr. Abel lists the difference as "not significant" but does not supply a "p value"; we thus cannot gauge what the actual probability is that the difference is explained only by chance.^[25] The finding of no significance is particularly puzzling because, according to Dr. Abel's other findings, users of "erotica" commit the same number of sex crimes per month (actually 21 percent more, but once again the difference is listed as "not significant") and maintain their paraphilia for more total months. Mathematically this would seem to compel the conclusion (already suggested by the statistics on "mean number of sex crimes") that by the end of their paraphilia, the group using "erotica" will have committed more total sex crimes than nonusers. That indeed seemed to be the gist of his oral testimony, where he explained the "price" paid by sex offenders who use "erotica" to reduce their desire to commit sex crimes:

...when you use the deviant fantasy in order to ejaculate, instead of attacking a kid or raping someone, it does transiently stop you from carrying out that behavior. In many cases, that is the case, but it's a transient phenomena. And in so using that tactic, the price you pay is maintenance of your arousal. That is your arousal stays strong and will get a little stronger. So over time you are more likely to maintain your arousal over a longer period of time, that means you can commit more acts.^[26]

In view of these internal tensions, Dr. Abel's results are extremely difficult to use in their present form.^[27] They seem clearly to indicate, and Dr. Abel said as much, that use of "erotica" by sex offenders (outside a treatment setting) is not "helpful."^[28] On the other hand they do not seem to rule out, Dr. Abel's protests to the contrary notwithstanding, the possibility of some important statistical relationship between use of sexually explicit materials and commission of sex crimes by this population.

The possibility of such a relationship is clearly enhanced by several other relevant studies. Thus Dr. William Marshall (1985) found in an outpatient study that a far higher percentage of sex offenders currently use "hard-core" pornography than do a group of demographically similar "normals." Professor Diana Russell found high correlation in her study of 930 randomly selected adult women: a surprisingly high number of women victimized by wife rape and stranger rape who said pornography had played a substantial role in the event. A similar survey of 200 prostitutes by Silbert and Pines (1982) found that 24 percent of the large number who had been raped "mentioned allusions to pornographic material on the part of the rapist"-this without any questioning or prompting by the interviewer. Law enforcement witnesses we have heard have also consistently stated that pornographic materials are routinely found on the person of, or in the residence of arrested rapists. While all of this is, like Dr. Abel's evidence, "merely" correlational data, it suggests reason for further inquiry and research on the use of sexually explicit nonviolent materials by sex offenders.

An overview of "correlational" evidence available to us ultimately leads to only one firm conclusion. A highly significant, and not obviously spurious statistical relationship exists in the United States between state "adult magazine" circulation rates and sexual violence. That relationship may be explained by a causal connection or it may not; only careful attention to other forms of evidence can indicate which explanation is more plausible. Because "adult" magazines contain relatively little violence,^[29] their connection (if one exists) to rape rates makes an excellent "test case" for considering the possible effects of the broader class of nonviolent but sexually explicit materials.

No clear statistical relationships exist, on the other hand, between cross-cultural measures of rape and sexually explicit materials, although such measures if anything tend slightly to support some relationship between the two. Nor is there undisputed evidence regarding the correlation of "erotica" use by sex offenders and commission of sex crimes; it is at least strongly arguable, however, that such a relationship exists. Other sources of information may prove more informative in evaluating these ambiguities.

Statement of Father Bruce Ritter