WORCESTER — A state trooper found guilty of indecent assault and battery was sentenced Thursday to 1 to 2 years in state prison.

A 12-member jury found Trooper Jason M. Willard of Auburn guilty of one count of indecent assault and battery Wednesday after a three-day trial. The jury of six men and six women acquitted the 40-year-old suspended trooper on two additional counts of indecent assault and battery and two counts of open and gross lewdness.

Judge Daniel M. Wrenn imposed the 1 to 2-year prison term Thursday morning, after hearing sentencing recommendations from lawyers for the prosecution and defense and impact statements from the victim and members of her family.

After the sentencing, Col. Timothy P. Alben, superintendent of the Massachusetts State Police, said Trooper Willard has been suspended without pay since Sept. 2012. Col. Alben said the process of firing Trooper Willard is underway.

"Willard's criminal act, as proven beyond a reasonable doubt to the jury, is an affront to the men and women of the Massachusetts State Police who work tirelessly, with integrity and honor, in their daily professional and personal lives," Col. Alben said in a statement.

The victim testified during the trial that Trooper Willard sexually assaulted her on three occasions and twice exposed himself to her between August and November of 2008, when she was 18. Trooper Willard had previously sent her a series of sexually explicit instant messages telling her he wanted to see her naked and have sex with her in the back seat of his cruiser, according to the now 24-year-old woman, who is a relative of the trooper's ex-wife, Kelly Willard.

Trooper Willard, who joined the state police in 2002 and was stationed at the Sturbridge barracks, was suspended without pay after being indicted on the charges in 2012. Still pending against him in Central District Court are two counts of violating a restraining order.

Judge Wrenn ordered that Trooper Willard be held overnight without bail after the jury returned its verdicts late Wednesday afternoon.

Defense lawyer Michael H. Erlich told Judge Wrenn he found his client in tears when he met with him Thursday morning in the courthouse lockup.

"One night behind bars for a state trooper is like 100 for anyone else in this courtroom," Mr. Erlich told the judge before asking that Trooper Willard be placed on probation with a suspended sentence and spared a period of incarceration in jail or prison. Mr. Erlich said his client's safety would be in jeopardy behind bars because of his position as a law enforcement officer.

"The fear of walking out of his cell and being stabbed was extremely real for him," the defense lawyer said of the officer's overnight stay at the Worcester County Jail and House of Correction in West Boylston.

Mr. Erlich said Trooper Willard graduated from St. John's High School and attended Northeastern University and Worcester State University before an eight-year stint in the Marine Corps. A father of four young children, Trooper Willard worked for the Spencer and Auburn Police departments and at the county jail prior to joining the state police, according to his lawyer.

Mr. Erlich said his client had no prior criminal record and noted that advisory sentencing guidelines called for a period of incarceration ranging from 0 to 24 months.

Assistant District Attorney Terry J. McLaughlin recommended that the trooper be sentenced to 2� years in the House of Correction with one year to serve and that the balance of the sentence be suspended for 3 years with probation. The prosecutor asked that Trooper Willard be ordered to undergo a sex-offender evaluation and any related treatment recommended by the Probation Department as one of the conditions of probation.

The victim's mother described the convicted trooper as "a disgusting coward" and "a predator" in her impact statement.

"Your job was to enforce the law, not to break it," the victim's uncle said to Trooper Willard in his impact statement. Saying he made the victim's life "a living hell," the uncle asked the judge to sentence the suspended trooper to 5 years' imprisonment, the maximum sentence for indecent assault and battery.

He said such a sentence would "send a message that law enforcement officers are not above the law."

"Your job was to serve and protect. However, you used that job to serve your perverse needs," said the trooper's ex-wife.

"You hid behind a badge and you thought that you were untouchable," the victim said in her impact statement. "I hope Jason is made to seek help until he realizes he is sick.

"No one's self-respect should be taken from them and that's what Jason did," she told the court.

Contact Gary V. Murray at gmurray@telegram.com. Follow him on Twitter @GaryMurrayTG