HAVERHILL, Mass. — Donna Burleigh fought back tears Tuesday as she remembered her brother, critically injured in an accident last year that prosecutors say was caused by a texting teenage driver.

Donald Bowley Jr. of Danville, N.H., who died 18 days after the crash, hated talking on the phone and didn't own a cell phone, so he would often stop by to visit with his sister at her home in Kingston, N.H.

“He was well-loved by his family. He was a good man. He worked hard,” Burleigh testified Tuesday as 18-year-old Aaron Deveau went on trial in Massachusetts' first motor vehicle homicide case involving texting and driving.

Deveau, of Haverhill, was 17 at the time of the accident on Feb. 20, 2011. He faces charges of motor vehicle homicide and negligent operation causing bodily injury due to electronic messaging.

Deveau is accused of texting when the 2001 Chevy Malibu he was driving crossed the center line on River Road in Haverhill and hit Bowley's car head-on. Bowley, 55, was driving; his girlfriend of four years, Luz Roman, was in the passenger's seat. Deveau told police that he swerved to avoid hitting a car in front of him.

The trial comes two years after New Hampshire and Massachusetts passed laws making it illegal to text while driving.

In her opening statements in Haverhill District Court, Assistant District Attorney Ashlee Logan told jurors that Deveau was texting at the time and had sent as many as 193 text messages that day.

She told jurors that they will have an opportunity to review cell phone records during the trial and will see that Deveau was texting in the moments before the accident, which occurred between 2:35 and 2:36 p.m.

“Two texts at 2:33, a text at 2:34, a text at 2:35 are being sent back and forth, back and forth between the defendant and (another person). Those times are going to be very, very important,” Logan said.

During his opening statements, defense lawyer Joseph Lussier agreed that the case is all about timing.

“We're going to argue about timing because timing in this case is everything,” he told jurors.

Lussier, who has raised questions about whether the accident ultimately caused Bowley's death, said there will be differences of opinion regarding some of the evidence presented. He asked jurors to consider whether Deveau is criminally liable for the accident.

“Did what Mr. Deveau do in operating a 3,500-pound car on a public highway, was it reasonable at the time or was it criminal?” he told the jury.

Deveau plans to testify in his own defense, most likely early next week.

The prosecution argues that Bowley suffered a brain injury that was so severe that he would not have survived.

During her testimony, Burleigh said doctors told the family that there was “no hope” and that he would not “get any better and eventually it would take his life.” Bowley's family decided to have him taken off life support and he died on March 10.

Dr. Kimberley Springer of the chief medical examiner's office testified that Bowley died from complications caused by the injuries suffered in the accident.

“The defendant did not mean to kill Mr. Bowley. He did not mean to seriously injure Ms. Roman. That is not what the Commonwealth has to prove. His intent is irrelevant because the statute is about the ways that one drives their car ... What is relevant is what did the defendant specifically do while he drove his car,” Logan told jurors.

The trial continues Wednesday.