Just weeks before he would have faced trial, Jesse Sullivan pleaded guilty to murdering his half-brother, Zackary Sullivan, in January of last year. 

Sullivan, 33, was indicted last spring on first- and second-degree murder charges, among others, after he was accused of shooting his brother in the back of the head inside the pickup truck of another brother, Rory Sullivan. Pleading guilty to the lesser charge of second-degree murder, Jesse Sullivan faces a sentence of 53 years up to life in prison, according to court documents. He also pleaded guilty to charges of falsifying physical evidence, being a felon in possession of a deadly weapon and reckless conduct with a deadly weapon. He will be sentenced in Merrimack Superior Court on June 18. 

In New Hampshire, people convicted of first-degree murder face life imprisonment without parole, while the sentence for second-degree murder is up to life imprisonment, retaining the possibility of parole, as determined by the court.

Court documents show that prosecutors collected substantial evidence that Jesse Sullivan had shot his brother. 

Rory Sullivan — a half-brother to Jesse and full brother to Zackary — told police that Jesse had shot Zackary in the back of the head as the three were in Rory’s pickup truck on the evening of Jan. 16, 2024. With Jesse sitting in the passenger-side backseat behind Zackary, Rory said he heard a loud pop and looked over to see Zackary’s head slump down.

Rory called Concord Police to the Dunkin Donuts on Manchester Street around 7:10 p.m., and they arrived to see Zackary on his back outside the parked pickup truck with Rory kneeling over him with his hands on his chest. They found a gunshot wound on Zackary’s neck, just below his hairline, and he was later pronounced dead at Concord Hospital.

The medical examiner determined that the wound had come from close range or contact. The state forensic lab said that a bullet fragment in the wound matched characteristics of rounds recovered from an Airport Road home that Rory said Jesse had fired into earlier in the evening.

The lab also found that two shell casings inside the pickup truck had been fired by a gun investigators discovered buried in the snow outside an apartment building next to the Dunkin Donuts. DNA examination of blood in the snow beside where the gun was found was a strong likely match for Jesse Sullivan. Surveillance footage timestamped to minutes after the police call showed someone matching Jesse’s appearance around the apartment building, and he was taken into custody there in the early hours of Jan. 17. 

The gun recovered from the snow was also a serial number match to one that had belonged to a family friend and that had been kept in their home, where Jesse Sullivan stayed ovenight a few weeks before. 

Rory Sullivan told investigators that Jesse Sullivan believed his younger brother had “ratted on him,” to the police about a fight that took place a few months before. Both Jesse and Zackary Sullivan were identified by police as part of that incident; Zackary was arrested and released on personal recognizance while a warrant for Jesse was outstanding. Court documents state that Jesse’s belief about his brother was “erroneous.”

Attorneys for Jesse Sullivan did not respond to a request for comment Tuesday.

Catherine McLaughlin can be reached at cmclaughlin@cmonitor.com.