A former Chicago official convicted in the red-light camera scandal should get a minimum 10-year prison sentence, federal prosecutors argue.

Federal prosecutors made that request ahead of John Bills' August 29 sentencing hearing, the Chicago Sun-Times reports.

"John Bills exploited the public trust to line his own pockets," Assistant U.S. Attorney Timothy Storino stated in a court memo. "He did so repeatedly and proactively over the course of about a decade. Since being caught, he has shown no remorse or contrition. He is thus deserving of a significant term of imprisonment."

Bills, a former top official in Chicago's Department of Transportation, was convicted in January on each of the 20 counts he faced for receiving bribes to help Redflex Traffic Systems, Inc. obtain red-light camera contracts with the city. The charges included extortion, bribery, wire and mail fraud, tax evasion and conspiracy.

The Chicago Tribune unearthed the red-light camera scandal, prompting the city to terminate its contract with Redflex in 2013.

Bills' attorney, who maintains that Bills was set up, is seeking a lesser sentence for his client, arguing in a court memo that "Mr. Bills was never a ringleader set out to mastermind an elaborate bribery scheme."

"He never had the authority or power," the memo added.