Federal law bans gun purchases by people convicted of or under indictment on felony charges, fugitives, the mentally ill, those with dishonorable military discharges, those who have renounced U.S. citizenship, illegal aliens, illegal-drug users, and those convicted of domestic violence misdemeanors or under domestic violence restraining orders. State laws add other categories; for Pennsylvania, that includes repeated drunken driving and some juvenile offenses.