A former Fairfield resident was convicted Monday of possessing more than 300 video files of child porn.

John Spence, who previously lived on May Street, handed his car keys and sunglasses to his lawyer and then put his hands behind his back to be handcuffed by marshals after a jury found him guilty of first-degree possession of child pornography at Bridgeport Superior Court.

In the back of the courtroom, his mother muttered, "Someone is going to pay for this."

Spence, 41, faces up to 20 years in prison when he is sentenced Nov. 19 by Superior Court Judge Maria Kahn.

Senior Assistant State's Attorney Cornelius Kelly later thanked State Police Detective David Aresco for his work in the case.

"This is a significant problem in our society that needs to be addressed and the Connecticut State Police are making a supreme effort to stem the tide of child pornography," Kelly said.

"Unlike a drug case where police seize a quantity of cocaine and then it is off the street, these images remain on the Internet forever," he told the jury during his summation.

Spence, a driver for the discount Megabus line, was arrested last year after State Police said they traced the transfer of child porn images to his computer. On June 13, 2012, police executed a search warrant on Spence's former May Street home.

While there Kelly said Spence asked to speak to investigators privately. He then admitted to viewing and downloading child porn for the past three or four years.

"I'm not looking for any particular age when I download child pornography, I just get whatever I can get," police said he told them.

Spence did not testify at trial, and his lawyer claimed State Police had coerced the alleged confession from him.

The jury of three men and three women deliberated two hours before announcing it had a verdict.

Kelly said police subsequently found 340 video files on Spence's computer that contained child pornography.

More than 40 of the images were of children previously identified as victims of child abuse, he said.