RIVERHEAD, N.Y. — A man caught in an online sex sting in which a former Miss America posed as a teenage girl has pleaded guilty two weeks into his trial.

Lawrence Carulli, 49, had argued that he was exploited for the sake of a true-crime television show. But he admitted Thursday to attempted dissemination of indecent material to a minor.

Carulli faces an expected five-year prison term. His sentencing was set for May 13.

“My best defense was going in front of a judge and hoping she would see my side,” Carulli said outside the courtroom.

Carulli acknowledged he solicited sex online and drove from his home in Brown Mills, N.J., to Long Island for a liaison. He insisted he believed his correspondent was 24, but prosecutors maintained he knew she was 14.

Unbeknownst to Carulli, the electronic enticement was part of a police operation in which Miss America 2007 Lauren Nelson [pictured] pretended to be a lonely 14-year-old girl. She chatted with men online and on the phone, drawing them to a home where a camera crew from television’s “America’s Most Wanted” was waiting. An episode involving the sting aired in 2007.

Carulli sensed something was wrong when he got to the house and left. He was arrested at a highway exit three miles away. His defense lawyer, Robert Macedonio, had called the arrest a stunt for the media, suggesting his client was coerced into making an incriminating statement and paraded before the “America’s Most Wanted” cameras.

Carulli’s guilty plea came after parts of a graphic chat-room transcript was read in court, and several police officials testified that Carulli confessed that he thought he was arranging for sex with a minor.

Seven other men also have pleaded guilty in the sting.