Ten states have recently passed laws requiring voters to present government-issued photo identification before they can vote. Ostensibly, these laws are to prevent voter fraud. However, a study by nonpartisan university researchers at NYU's Brennan Center for Justice has shown that voter fraud is microscopic (e.g., 0.00004% of the votes in the 2004 Ohio election were fraudulent); the penalty for getting caught is so large (5 years in prison), and the effect of one vote so small, that nobody risks it. The very occasional fraudulent vote is invariably from an ex-felon or green-card holder who mistakenly thought he had the right to vote.