Who investigates and prosecutes federal crimes?
For the most part, federal criminal offenses are investigated by agents of federal agencies such as DEA, ATF, Secret Service and others. Occasionally, state law enforcement officers work in conjunction with federal agencies. Federal crimes are usually prosecuted by the United States Attorney’s Office for the district where the crime occurred. Sometimes a prosecutor for the United States Department of Justice, or an agency such as the Environmental Protection Agency will participate in a federal prosecution.