Melanie Cooper will spend Christmas in prison after admitting to covering up the murder of her allegedly abusive stepfather, who was shot to death by her Hopkinton High School friend in 1985.

Judge Robert Lynn sentenced Cooper to three to six years in prison, despite prosecutors’ suggestions to suspend the sentence because of Cooper’s cooperation in the case against Hopkinton’s Eric Windhurst, who’s serving 15 to 36 years in prison for the murder of Hooksett’s Danny Paquette.

Cooper, who was taken to state prison after the Friday, Dec. 1, hearing, will serve a minimum of three years before she’s eligible for parole, said Senior Assistant Attorney General Jeffery Strelzin.

Strelzin said at least six witnesses – including investigators of the murder case – spoke on Cooper’s behalf before her sentence was handed down.

According to news reports, Lynn wasn’t convinced that Cooper, who was 15 when she accompanied Paquette to near the site of the shooting, was unaware of Windhurst’s intent to murder.

Cooper, who’s been living in Evanston, Wyo., with her husband and five children, has told investigators she was physically and sexually abused by Paquette in years prior to the murder.

Records show that Cooper and her mother, Denise Paquette, feared Danny Paquette’s alleged abuse and fled to Alaska before Cooper returned to New Hampshire to live with her aunt just prior to the murder.

Prosecutors have maintained that Windhurst, a builder and Cooper’s soccer teammate, was driven to the murder to protect Cooper, and by revelations about his own father’s alleged sexual abuse of relatives.

Paquette’s brother, Victor Paquette, said the sentencing “put a period at the end of the sentence, instead of just an open space.”

“There’s no victory party for the Paquette family,” he said, “just a small sense of satisfaction that justice has been served.”

The murder

Windhurst, then 17, picked up Cooper in a Volkswagen Rabbit on the morning he shot Paquette, who was 36.

According to police interviews with Cooper, the two drove to the woods near Paquette’s home, and Windhurst removed a gun from the car and rubbed mud on its license plate. He and Cooper stopped and talked at a stone wall. According to court records, Windhurst put a piece of gum in his mouth and told Cooper he was going to “do it” when the flavor went away. Cooper told investigators Windhurst then walked deeper into the woods before she heard a gunshot.

Windhurst then returned to Cooper, and the two drove away, with Windhurst urging Cooper to keep her head low, according to court records.

The case

In 2004, investigators made what Strelzin called a “surprise visit” to Cooper’s home for an interview.

It was then that Cooper opened up to police, and abandoned her previous alibi that she and Windhurst were at a sporting event in Plymouth during the time of the shooting.

Cooper eventually agreed to a polygraph test, and allowed investigators to tap into phone calls between her and Windhurst. “I think she just felt it was the right thing to do,” Strelzin said of Cooper’s cooperation.

Her testimony led police to interviews with more of Windhurst’s former friends and family members, at least five of whom told police Windhurst admitted the murder to them, according to court records.

Victor Paquette said the “real heartbreak” of his brother’s murder is that it took 20 years for such testimonials to come out.

“I was really disappointed this went on as long as it did when so many people knew,” he said.

Strelzin confirmed Cooper does have the option of calling on a state sentence review board to review her case, though she can’t appeal the decision because of her guilty plea.

The sentence review board, if called on, could either extend or shorten Cooper’s sentence, Strelzin said.