A New Hampshire prep school graduate convicted of sexually assaulting a 15-year-old freshman as part of a game of sexual conquest is seeking a new trial, saying his former lawyers were ineffective.

Twenty-year-old Owen Labrie was convicted in August of misdemeanor sex assault charges and a felony charge of using a computer to lure an underage student for sex. The felony carries the mandate to register as a sex offender for life. He was sentenced to a year in jail.

In her motion, Jaye Rancourt says Labrie's lawyers didn't challenge the computer offense until after his trial and conviction.

His former lawyers included J.W. Carney, who also represented Boston gangster James "Whitey" Bulger. A message was left Wednesday seeking comment from Carney.

Labrie was arrested in 2014 days after graduation from St. Paul's School in Concord, NH.