Increased Groping on Tokyo Trains

An application of the economic analysis of crime and punishment can be found in this story from the BBC (thanks to JC for pointing out the link here). People are packed together pretty close during rush hour, leading to many groping opportunities.

Reported incidents of sexual assault on Tokyo's trains have reached a record high, with 2,201 cases last year. This is up from 2,058 cases in 2003 and is triple the number of such incidents recorded in 1996.

The authorities have tried to reduce groping incidents by adding women-only cars. At the same time, they believe that groping incidents may not have increased as much as the number of groping incidents reported. One reason there have been more reported incidents is that

Reporting culprits has been made easier by the introduction of mobile phones with a camera facility, which allow the victim to take a photo of the molester.

But just in case it isn't all due to increase reporting of molestations,

The police said they planned to step up patrols on trains and platforms and urge rail companies to increase the number of single-sex train cars.

All of these changes are designed to increase the probability of detection of molesters. Increasing the amount of punishment might also have this effect.