A 63-year-old man was given a 12½-year sentence after admitting he fatally shot a Twin Cities man at an employee Christmas party at a popular North Shore resort.

Kirk L. Bigby, 63, from nearby Silver Bay, was sentenced Wednesday in Cook County District Court after pleading guilty to unintentional murder in the 2015 killing of 35-year-old Marcus L. Roberts, of Bloomington at the Bluefin Bay resort.

With credit for time in jail since his arrest, Bigby will serve the first 7¼ years of his punishment in prison and the balance on supervised release.

Roberts was at the resort in the small town of Tofte on Dec. 9, 2015, with a casino gambling party rental company when he was shot outside shortly after midnight. The rental company was providing entertainment for the annual Christmas party being held for the resort's employees.

As the party was ending, several people stepped outside from the resort's Bluefin Grille, and that's when Bigby "came into physical contact" with Roberts and shot him with a handgun, the Sheriff's Office said in a statement soon after the killing.

The Sheriff's Office said Bigby, who worked delivering firewood to guest rooms, had a government-issued permit to carry a firearm at the time.

In a court document outlining details of the plea deal, Bigby acknowledged that "intoxication is not a defense" for killing Roberts and that he was waiving his right to claim self-defense. However, the filing continued, "I am still able to argue that the victim was the first aggressor."

Roberts, who attended Minneapolis South and Redwood Valley High School, was the father of six children and had seven siblings.

Paul Walsh • 612-673-4482