CONCORD, NH (CBS) – Owen LaBrie, the former New Hampshire prep school student convicted of sexual assault, is seeking a new trial.

LaBrie argues that one of New England’s most prominent defense attorneys, J.W. Carney, poorly defended him.

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The attorney won LaBrie an acquittal on rape charges but he was found guilty of using a computer to lure an underage girl for sex.

The conviction requires LaBrie to register as a sex offender.

J. W. Carney was replaced with Robin Melone.

“We feel really good about how it went today, so we’ll see,” said Melone.

In court, Melone put another former defense attorney on the stand, Jaye Rancourt.

Jaye Rancourt in Merrimack County Superior Court, Feb. 21, 2017. (WBZ-TV)

Jaye Rancourt in Merrimack County Superior Court, Feb. 21, 2017. (WBZ-TV)

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Rancourt said Carney was so ill-prepared for LaBrie’s rape trial, that it made her teary to think about the moment.

“I’m sorry. That was possibly the most terrifying moment of my legal career,” said Rancourt.

“I was sitting in the room thinking I was going to have to go in that court room and interrupt this trial and step in and say ‘I can’t let this go on.’”

Rancourt’s statement called into question the reputation of the well-established criminal lawyer, who represented gangster Whitey Bulger in his historic murder trial.

In LaBrie’s case, Rancourt said Carney failed to argue against the computer felony he was convicted of, which makes him register as a sex offender for life.

She says the charge is based on internet emails, while communications with his victim were on a local server. The St. Paul school owns the website that they called “intranet” not “internet.”

Rancourt says Carney overlooked evidence that would have called the victim’s credibility into question, like a picture that shows her doing splits before she said she was sore from the assault.

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