 In a 2009 study co-authored with Robert Erikson, she found inconsistent and weak evidence that voter ID laws reduced turnout.She has argued in her 2010 book, "The Myth of Voter Fraud", that voter impersonation is very rare in the United States—in fact, when researching the subject while writing the book, she identified only one case of voter impersonation from 2000 to 2005, involving a teenager in New Hampshire who voted as his father.In the same book, she found that in 2005, the federal government charged far more people with violating migratory bird laws than with committing voter fraud.