The man driving behind Lipford was 35-year-old Daniel Stonebreaker of Cove City, the investigating trooper said.
The investigation into whether charges will be filed is ongoing.
The trooper plans to meet with the district attorney this week.
Neither speed nor alcohol was a factor in the crash, the trooper said.
A grandmother was killed in a fatal crash Friday night on Highway 70 in Craven County. The accident happened about five miles west of New Bern.
According to Highway Patrol, Melba Lipford, 63, was travelling westbound with her five-year-old grandson in a Mercury Mountaineer. A man at the crash scene told authorities he was driving in a GMC Acadia behind Lipford's SUV. He says he looked down and when he looked back up, he rear-ended Lipford.
Lipford lost control of her vehicle and crashed into several pine trees on the side of the highway. A purse and dozens of personal items were strewn across the ground, marking the spot where the Mountaineer ran off the road. The accident happened around 8:30 p.m. and involved no other vehicles.
Lipford's grandson survived the collision, and witnesses described him crying out for his grandmother when he was taken out of the SUV. New Bern firefighters said the grandson's car seat saved his life.
Lipford was following her husband, who turned around when he noticed his wife was no longer behind him. He arrived on the scene, but could do nothing to help his wife.
It took crews nearly an hour to remove Lipford's body from the twisted wreckage.
Authorities said alcohol and speed were not factors in the collision.