Minnesota dad gets 6 months max for death of toddler shot by 4-year-old brother with unsecured gun

A reworked guilty plea agreement resulted Friday in a maximum of six months in jail for a southern Minnesota man whose 2-year-old boy was fatally shot by his 4-year-old brother with an unsecured gun.

Colton Mammenga, 34, of Welcome, was sentenced by Martin County District Judge Michael Trushenski in connection with the Oct. 15 shooting of Matthew Alshaikhnasser in a moving pickup truck.

Trushenski set aside an 18-month prison term and ordered Mammenga to serve 90 days of his jail sentence starting next week. He’s also scheduled to serve the remaining 90 days starting a year from now, but he can have that time waived if he complies with the terms of his five years of probation. Those terms include 500 hours of community service, which calls for him to speak publicly about firearms safety.

In April, Trushenski tossed out the deal reached a month earlier between County Attorney Taylor McGowan and the defense. The terms of the initial plea deal called for the dismissal of manslaughter and attempted manslaughter charges and one count of negligent storage of a gun. In exchange, Mammenga agreed to plead guilty to felony child endangerment.

The deal also called for no jail time, no fines and for the plea to be entered under a stay of adjudication, meaning the conviction would have come off his record after adhering to the terms of his probation.

These sentencing terms generally fell in line with the revised plea deal reached in July that required jail time and have the conviction remain on his record.

In a letter to the judge before the first and more lenient plea deal was rejected, McGowan explained that “a young child died as the result of an action that was accidental, yet at the same time criminal. Mr. Mammenga is someone who loved that child and is no doubt punishing himself more than the state court could ever do.”

According to the charges:

At the time of the shooting, Mammenga was in the pickup with the two boys and their mother, who was in a relationship with Mammenga. A deputy found the pickup outside Fairmont and pulled it over. Mammenga exited the vehicle holding Matthew, who was shot in the head.

Mammenga performed CPR before an ambulance crew arrived and took over. He told law enforcement the 4-year-old accidentally shot Matthew while the truck was in motion, and the gun was still in the back seat with the older child. The injured boy was taken by air ambulance to a Rochester hospital, where he died two days later.

Three rifles and ammunition and magazines for those weapons were also seized from the truck by law enforcement, according to court records filed by the Sheriff’s Office.

The 4-year-old told a deputy he got the gun from the front seat when the boys were left alone in the truck while Mammenga and the mother went inside to retrieve something. Mammenga told police he had left his gun in the passenger side door pocket before going inside.