BROOKLINE – A New Hampshire State Police accident reconstruction team has been called in to probe the fatal crash that took the life of a 30-year-old Brookline mother of three girls the day before Christmas.

Brookline Police Chief Bill Quigley said the investigation has been handed over to state police, who will return Monday to inspect the vehicles involved in the crash and conduct additional interviews.

“They’ve still got a lengthy investigation ahead of them, and any charges that may come from this – that will be determined upon conclusion of the state police investigation,” Quigley said.

The Hillsborough County Attorney’s Office will determine whether charges are warranted against the driver who police say rear-ended Katie Hamilton on Route 13, sparking a three-car collision.

Hamilton was either stopped or slowing down to make a left turn onto Milford Street – right outside the town’s public safety complex – when she was hit from behind by a silver 2009 Toyota pickup truck, police said. Her SUV was pushed into oncoming traffic and was struck by a Ford F250 truck. She was pronounced dead at the scene.

Quigley said it appears the driver of the Toyota – 31-year-old Greg Cullen, of Milford – swerved to the right just before hitting the back of Hamilton’s vehicle. He said police are investigating whether cellphone usage or another form of driver distraction was a factor in the incident.

“We know that it’s a 50-mile-per-hour road, so we know that excessive speed was not an issue, and after speaking with the other two operators … we were able to rule out any impairment on their part,” he said.

County Attorney Patricia LaFrance declined to comment on the evidence police have gathered to date. She said in other cases, fatal motor vehicle accidents have led to charges ranging from negligent homicide to manslaughter.

In another recent example, a 20-year-old Mont Vernon man was arraigned Tuesday on a negligent homicide charge after allegedly striking and killing a man in Amherst while texting on his phone. The charge is a Class B felony and carries penalties of between 31?2 years and seven years in jail.

The Hillsborough County Attorney’s Office also has levied manslaughter charges in the past – a crime that carries a potential jail sentence of up to 30 years.

“My office is consulting with the New Hampshire State Police, and – if and when charges are brought – we will be speaking with the police about that,” LaFrance said.

Quigley said Hamilton’s family is well-established in the small town of roughly 4,000. Her father, Steve Whitcomb, is a longtime volunteer firefighter and was among the first responders who rushed to assist after Tuesday’s crash.

Hamilton was born in Nashua on Feb. 26, 1983, and raised in Brookline in a home on Milford Street by her parents, Steven and Catherine E. Whitcomb. She attended local schools and graduated from Hollis Brookline High School in 2002.

A mother of three young girls, Hamilton lived with her husband, Liam, on Bond Street. Hamilton was a devoted mother and enjoyed spending time with her three girls – Madalyn, Lillian and Caleigh Hamilton – according to her obituary. She enjoyed trips to Disney World and Santa’s Village with her children and also enjoyed fishing, going for long walks in the woods and vacationing in Newfield, Maine.

“She was a sweet, kind mother with a heart of gold,” her daughter was quoted saying in her obituary.

Hamilton was an apprentice plumber and had worked with her father for more than eight years at Whitcomb Plumbing & Heating. She also practiced Reiki and was recently certified as a Zumba instructor.

Hamilton’s father volunteered at the Brookline Fire Department for more than 20 years, and Katie Hamilton became a regular presence around the fire department, according to Fire Chief Charlie Corey. Corey said she volunteered at numerous fundraisers and showed up at emergencies around town to feed the fire crews.

“It’s a tight-knit group of people on the fire department and in town,” Corey said. “You know, a lot of families have been here for a lot of years, and everybody’s grown up together, so it’s a very tight group.”

A fund was established Thursday at a local TD Bank branch in Hamilton’s memory. An employee said a family friend opened the account in the morning to provide assistance to Hamilton’s family.

Donations can be made to The Hamilton Fund, c/o TD Bank, 104 Route 13, Gazebo Square, Brookline, NH 03033. Those who wish to share a memory of Hamilton or offer a condolence to family members are encouraged to visit www.smith-heald.com.

Visiting hours will be held Sunday at Heald Funeral Home, located at 63 Elm St. in Milford. A funeral will take place on Monday at 10:30 a.m. in Lakeside Cemetery on Mason Road in Brookline, followed by a celebration of her life at the Brookline Event Center, located at 32 Proctor Hill Road, Route 130.

Jim Haddadin can be reached at 594-6589 or jhaddadin@nashuatelegraph.com. Also, follow Haddadin on Twitter (@ Telegraph_JimH).