HAMMOND, Ind. — A lawyer for a northwestern Indiana on trial for federal bribery charges told jurors that the FBI tried to buy a crime where one didn’t exist.

Federal prosecutors opened the trial of Lake County Sheriff John Buncich on Monday by saying they would present recordings of him receiving thousands of cash in envelopes as bribes from tow truck operators seeking towing business.

One of the first witnesses was a former Merrillville police officer and towing company owner who testified FBI agents recruited him to pay bribes to Buncich and record the meetings. Scott Jurgensen testified the FBI paid him more than $130,000 over five years, including bribe money.

Buncich is a Democrat and was elected in 2015 to his fourth term as sheriff of Indiana’s second-most populous county.