Sheriff, Cook County, IL
Tom Dart is sheriff of Cook County, IL, serving in his third term in a position he was first elected to in 2006. As head of the country’s second-largest sheriff’s department, he has worked to reduce the number of nonviolent offenders detained at the Cook County Jail while spreading awareness nationally about the criminalization of mental illness. Dart was previously chief of staff to former Cook County sheriff Michael Sheahan and an Illinois state representative, appointed to a vacancy in 1991 and then elected to and serving in that seat from 1993 to 2003. TIME named Dart one of its 100 Most Influential People in the World in 2009.