Counting Lewd's utility

It's currently legal in New Zealand to post online racy pictures of your ex. The Law Commission recommends changing that:

The commission also recommends the exemption for personal or domestic information should not apply if the collection or disclosure of the information would be highly offensive.

The change would deal with situations such as when a person posts naked photographs of their ex-partner online without consent.

Privacy Commissioner Marie Shroff welcomed the report. "It will put, for the first time, the careless, the predatory and the criminal on notice," she said. "There will be consequences if you misuse our information."

I'm not particularly opposed to the law change. But I'm near certain that the Law Commission won't have weighed the benefit provided to voyeurs of the current legal framework. David Friedman argues, persuasively, I think, that we have to count all the benefits in the utilitarian calculus lest we wind up assuming our conclusion:

If instead of treating all benefits to everyone equally we first sort people into the deserving and the undeserving, the just and the unjust, the criminals and the victims, we are simply assuming our conclusions. Benefits to bad people don't count, so rules against bad people are automatically efficient. We cannot deduce moral conclusions from economics if we start the economics by assuming the moral conclusion.

It wouldn't surprise me if the utilitarian calculus found the law change to be efficient. Presumably, if the taking of private photographs has benefits for the couples involved, willingness to have such photos taken would depend on the likelihood of future dissemination. Further, some couples that would do better to split up may stay together, inefficiently, because of the hostage problem posed by the photographs' existence. It's entirely plausible that the losses to voyeurs are smaller than these gains. But I rather doubt that anybody's sought to measure either side.