AUGUSTA — A man who served 20 years for murdering his mother will spend three-and-a-half years in prison after he accosted a clerk in an adult bookstore in Waterville last year while wearing only socks and sneakers.

Scott L. Thompson, 41, of Waterville, was sentenced to six months behind bars on an indecent conduct charge — the maximum sentence for the misdemeanor — and ordered to serve it after he is finished serving three years related to an earlier burglary charge. He was out on probation on the burglarly conviction when the most recent incident took place.

“We requested the maximum sentence that was available,” said Acting District Attorney Alan Kelley. “This was a situation where we view Mr. Thompson as being very dangerous. Certainly it would be beneficial to have him supervised when he’s released, but he’s demonstrated there’s no way of protecting the public when it comes to him.”

Thompson was arrested last September after he walked out of the video viewing area of the First Amendment Adult Store in Waterville while masturbating, according to an affidavit filed with the court.

In a sentencing memo, Thompson’s attorney, Kevin Sullivan, told Justice Michaela Murphy that his client was at the store “doing there what he was invited to do, but he overstepped his license by walking out to the front part of the store while having his genitals exposed, causing alarm to the store clerk.”

Thompson was convicted in 1991 of stabbing his mother to death in their East Winthrop home. The murder occurred in 1989 after Thompson, who was 17 at the time, was high on marijuana and had watched pornographic movies. He spent nearly 20 years in prison.

In 2009, he broke into Treasure Chest II adult store in Waterville and stole novelty items. Later that year he groped a woman in a Waterville store.

He had been on probation for two months following his conviction on burglary charges related to the 2009 crimes when he was arrested at the First Amendment store in Waterville on Sept. 4. He later pleaded guilty to indecent conduct.

On Tuesday, Thompson was in Kennebec County Superior Court to be sentenced on that charge as well as charges he violated his probation by committing that crime.

Sullivan asked that some probation time remain so Thompson will be supervised when he is released from prison. He said the more recent crimes occurred because Thompson was released without support or aid after serving the two-decade-long sentence for murder.

Sullivan, in his memo, warns that leaving Thompson unsupervised would mean nothing would prevent him from “doing the same thing again,” and that “expecting a different result is without logic.”

Betty Adams — 621-5631

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