DETROIT (AP) – A U.S. Postal Service contractor who fixed mail vehicles in Michigan and Ohio paid bribes for eight years before becoming an informant, a role that led to criminal charges against five people, the government said Friday.

In a court filing, prosecutors for the first time elaborated on the work of Joe Fawaz, whose Metro Diesel garage got more than $13 million in business from the Postal Service.

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He began cooperating a year ago and secretly recorded payoffs over the next few months, the government said. Five postal workers in vehicle maintenance were indicted last May, and two have pleaded guilty. Fawaz has not been charged.

Denny Robinson, a vehicle-maintenance supervisor, is asking a judge to dismiss the bribery case against him, claiming he was entrapped through “outrageous conduct” because of a family connection. Fawaz is related to Robinson’s mother-in-law, and the two have mixed at family gatherings.

Robinson is charged with accepting more than $65,000 in cash, free service on his cars, a 2001 minivan and a high-performance Ford Pinto from Fawaz. Assistant U.S. Attorney David Gardey said there was no entrapment.

Fawaz had been paying bribes to postal workers for eight years before becoming a secret “government agent,” and Robinson was getting them for four, Gardey said.

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He said Robinson, on a secretly recorded video, calls his $2,000 payments from Fawaz a “regular thing.” Robinson indicated that some trailers needed to be sent to another contractor because “it looks bad” if Metro Diesel fixes all of them, according to the government.

“At no time during any of the meetings … did the defendant even hesitate for a moment in accepting the cash from the private contractor,” Gardey wrote.

Fawaz has refused to comment on his cooperation with federal investigators. Besides Detroit, he also had a garage in Akron, Ohio.

In June, The Associated Press reported that his cooperation helped his wife, Sarah, get a light punishment in an unrelated fraud case involving kickbacks paid to mortgage brokers. Instead of prison, she was sentenced to eight months of house arrest and four months in a halfway house. A judge recently changed it solely to a year of home confinement.

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