First, it is possible that the ruling caused rapes to fall through an indirect effect involving inframarginal reallocation of police resources. If police stop arresting indoor sex workers (which we find), then these same police resources could be reallocated elsewhere in the agency including the policing of rape and other sex crimes.
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Second, we investigate whether changes in data definitions or data collection over this period could explain the findings, and fail to find evidence for this.
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Thirdly, decriminalization could reduce rapes among prostitutes by improving the bargaining position of female sex workers relative to clients. Recent work in economics has shown that changes in female bargaining threat points has the potential to reduce violence against women (Aizer, 2010; Stevenson and Wolfers, 2006). Several studies note that indoor sex workers report considerably lower risks of victimization relative to outdoor street walkers, who themselves report extremely high rates of victimization.
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The last hypothesis is related to the idea that some violent males think of rape and
prostitution as substitutes (Posner, 1992; Dever, 1996). When the judicial decision caused
supply to increase and prices to fall, violent males at lower segments of demand could
have shifted towards purchasing sex indoors and away from violence toward women. While
speculative, there is anecdotal evidence for this. In the 2010 documentary Happy Endings
which is about the efforts of Rhode Island to re-criminalize indoor sex work, there is a
scene where a sex worker claims that she believes the men she services would have raped
other women had they not come to see her.