Story highlights Defendant says he wishes he could take back "mistake"

Aaron Deveau is sentenced to serve a year in prison on charges

Deveau, 18, denied texting at the time of the crash

The crash fatally injured Donald Bowley, 55, and injured Bowley's girlfriend

A Massachusetts teen was convicted Wednesday of homicide as a result of texting while driving and will serve one year in prison.

In a landmark case for the state, Aaron Deveau , 18, was found guilty on charges of vehicular homicide, texting while driving and negligent operation of a motor vehicle in a 2011 crash that fatally injured Donald Bowley, 55, of Danville, New Hampshire, and seriously injured a passenger in Bowley's car.

"I made a mistake," Deveau said Wednesday after his mother told the district court in Haverhill, Massachusetts he would not intentionally hurt anyone. "If I could take it back, I would take it back."

Judge Stephen Abany sentenced the teen to two and a half years on the vehicular homicide charge and two years on the texting and causing injury charge. He will serve one year concurrently on both charges and the balance of both charges is suspended for five years. His license will be suspended for 15 years.

"There are no winners today," Essex County District Attorney Jonathan Blodgett said in a statement. "A beloved grandfather is dead. A once active woman can no longer work and is still racked with pain from her injuries and a young man is going to jail. When we get behind the wheel of a car, we are obligated to drive with care. ... As we saw in this case, in a split second, many lives are forever changed."

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In the February 20, 2011, accident, prosecutors said, Deveau's car crossed the center line on a street in Haverhill, which is in northeast Massachusetts near New Hampshire, and hit the vehicle Bowley was driving.

Bowley's girlfriend, Luz Roman, 59, was in his car with him and suffered serious injuries.

Haverhill Detective Thomas Howell testified the impact left the two "almost folded into the floorboards."

Bowley died March 10, 2011, after he was taken off life support.

"My brother received such head trauma that ... there was no hope for him," Bowley's sister, Donna Burleigh, said in court.

Roman talked about the incident's continued impact.

"Loss of sleeping, loss of my boyfriend. So many losses, I can't tell you how many," she told the judge.

Essex Assistant District Attorney Ashlee Logan argued that Deveau may have erased some of his texts or lied to police after the accident about when he was texting.

Deveau said after the crash in a taped interview with police, which was played in court, "I was tired. I was distracted. When I looked away for one quick second, I came too close to her and I was trying to hit my brakes."

His defense lawyer said authorities set out from the beginning to link texting to the crash, a cause-and-effect relationship that he contends is not valid.

Some 38 states ban text messaging for all drivers, while 31 prohibit all cell phone use by "novice drivers," according to the Governor's Highway Safety Association.