FAIRFIELD — There are some crimes that cross the line, even with accused criminals.

Nabbed in a Fairfield sting last year in which police say he thought he was about to have sex with a 13-year-old girl, 41-year-old John Dupee was confronted by a verbal barrage from the gallery as he prepared to plead guilty before state Superior Court Judge Robert Devlin in Bridgeport last Friday.

The catcalls and lewd suggestions directed to the former Norwalk letter carrier from the audience — many who themselves were waiting to go before the judge — got so loud that Devlin interrupted the plea hearing to kick some of them out of the courtroom.

Dupee, of Dover Street, Norwalk, faces up to four years in prison after he pleaded guilty to attempted sexual assault with a minor, attempted sexual contact with a minor and enticing a minor on the computer. He is scheduled to be sentenced May 13.

Dupee was one of 10 men caught up in a sting last October by Fairfield police, according to State’s Attorney John Smriga. The sting was put together by television personality Chris Hansen, known for his former “To Catch a Predator” reports on NBC, for a future show.

The 10 men, ranging in age from 19 to 64, who police said each came to a house in Fairfield expecting to have sex with either a boy or a girl, were arrested in the undercover operation. Five of the men arrested came from out of state. The rest are from Connecticut, including one from Fairfield.

Smriga said Dupee contacted someone he thought was a 13-year-old girl through a website and agreed to meet her at the Fairfield house to have sex with her.