Peña advised Arkansas Governor Bill Clinton on transportation issues during Clinton's successful 1992 presidential campaign, and Clinton chose Peña to head the United States Department of Transportation. Although he was going to leave Clinton's cabinet after Clinton's first term, Peña also served as Secretary of Energy for one year, from 1997 to 1998. In 1995 the Justice Department began a preliminary investigation into a California transit agency's awarding of a pension management contract to Peña's former investment management firm. However, Peña had cut all connections to his former company both before the contract and before becoming Transportation Secretary. On March 17, 1995 Janet Reno ended the investigation.