He is a white-collar criminologist. He rose to national prominence as a key figure exposing the "Keating Five" savings-and-loan scandal in 1989, in which five U.S. senators were found to have been involved in negotiating favors for Charles H. Keating, Jr., chairman of the Lincoln Savings and Loan Association, in exchange for campaign contributions. His subsequent book, "The Best Way to Rob a Bank is to Own One," is considered a classic analysis of corrupting influence of Wall Street on the federal government.