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Man pleads guilty, apologizes for crash that killed trooper

William Senne (left) pleaded guilty today  in Plymouth Superior Court to vehicular homicide in the 2011 death of State Trooper Ellen Engelhardt.

David L Ryan/Globe Staff

William Senne (left) pleaded guilty today in Plymouth Superior Court to vehicular homicide in the 2011 death of State Trooper Ellen Engelhardt.

BROCKTON — William Senne pleaded guilty today to vehicular homicide in the 2011 death of State Trooper Ellen Engelhardt, who was critically injured by Senne in a 2003 accident and died eight years later without ever having regained consciousness.

The plea brings an end to the high-profile case whose victim was the first female trooper killed in the line of duty.

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Judge Charles J. Hely, sitting in Plymouth County Superior Court, sentenced Senne to 2 1/2 years in jail, but gave him credit for time already served. In 2005, Senne began serving 2 1/2 years at the Plymouth County House of Correction after pleading guilty to reckless endangerment and causing bodily injury while driving drunk.

Senne, 29, was also sentenced to serve three years of probation and 500 hours of community service. He had already completed five years of probation and another 500 hours under his 2005 sentence.

The plea ended more than a decade of legal issues for Senne, who was a teenager when the accident occurred, inflicting severe brain damage on Engelhardt. Plymouth District Attorney Timothy Cruz brought the vehicular homicide charge against Senne upon the trooper’s death, igniting a controversy over whether it constituted double jeopardy since Senne had already pleaded guilty and served time for the crash. If found guilty at trial, Senne could have faced a 10- to 15-year sentence.

Engelhardt died in 201l, after eight years of being in a vegetative state.

Massachusetts State Police/AP

Engelhardt died in 201l, after eight years of being in a vegetative state.

“I’m glad this chapter is over,” Senne said after the court hearing. “I’m glad I don’t have the continuing risk of prosecution.” He said he pleaded guilty because “it’s the right thing to do, and it puts this behind me.”

Both prosecution and defense made it clear that Engelhardt’s daughter was not seeking further punishment for Senne. Only the trooper’s cousin, Sheila Faiella, was in court today. “I thought a little more [jail] time would have been good for him,” said Faiella, who lives in Marshfield.

Engelhardt was one of the first women to serve on the State Police. At 6 a.m. on July 26, 2003, she had pulled off Route 25 in Wareham to examine a guardrail as part of an investigation into an earlier accident.

Senne was driving to his summer job teaching sailing lessons on Cape Cod when he smashed into Engelhardt’s cruiser at nearly 100 miles per hour. Senne says he has no recollection of the crash, and had been awake nearly 24 hours before falling asleep at the wheel of his father’s Volvo.

Assistant District Attorney Frank Middleton, who has handled the case since the crash, said in court today that Senne had a .05 percent blood-alcohol level four hours after the accident. Under Massachusetts law, the limit for those under 21 is less than .02 percent.

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