A former FBI special agent pleaded guilty to stealing more than $136,000 that was seized during drug investigations. Scott M. Bowman, 45, on Monday admitted in a Riverside, California, courtroom to using the money for a three-week spending spree on things such as a car, plastic surgery for his wife, and a Las Vegas boxing match, prosecutors said. Bowman told coworkers he received a $97,000 advance on his inheritance from his father in order to conceal the theft. He pleaded guilty to one count each of obstruction of justice, falsification of records, witness tampering, and conversion of property by a federal employee. The former federal agent’s arrest led prosecutors to drop criminal charges against more than a dozen defendants in a case he investigated while he served on a task force targeting gang-related crime.