Dear Economist,

I am concerned at how violent films are these days and I think the censors should be much stricter in cutting out scenes of explicit violence. I was wondering if there is any support in economic theory for my view.

A concerned parent, Kent

Dear Concerned Parent,

If I watch a splatter-fest and it causes me to punch somebody, that’s about as good a definition of an negative externality as you can get.

The cinema doesn’t care, unless a fight breaks out at the popcorn stand.

Nor do I. Only the poor chap with the broken nose feels differently about it all, and his feelings are not going to be taken into account. Yet here, economic theory would prescribe not censorship, but a tax on violent films.

This argument assumes that the effect of a violent film is to provoke more violence. That is not clear. I understand that when people watch violent images in laboratory experiments, they become more violent. (I’m not sure how this is measured: maybe a few psychologists were forced to eat their clipboards.)

But what you are not considering is this: when the local bully-boys are in the cinema watching UltraDeath III: the Revenge, they are not drinking lager or getting into fights. A new piece of research from economists Gordon Dahl and Stefano DellaVigna shows that when a violent film is on at the multiplex, violent crime falls during the evening and stays lower until the next morning. If a slushy romance is screened, the thugs go to the pub instead and mayhem ensues. Dahl and DellaVigna reckon violent films prevent 175 assaults a day in the US.

This suggests that if you plan on banning them, you might want to find a distracting alternative.

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