Jessee Mackin waves to his family and friends after receiving his sentence of 5 1/2 years in prison in this 2019 file photo. Credit: Linda Coan O'Kresik

The Maine Supreme Judicial Court on Tuesday unanimously upheld the manslaughter conviction of a Millinocket man in the death of a 6-month-old boy more than five years ago.

Jessee Mackin, 37, was sentenced in November to 11 years in prison with all but 5 1/2 suspended in the death of Larry Earl Lord. The baby died of a skull fracture on May 7, 2015, the medical examiner’s office determined.

Mackin is incarcerated at the Maine Correctional Center in Windham, according to the Maine Department of Corrections. His earliest possible release date is Feb. 2, 2024.

The child’s father, 40-year-old Anthony Lord of Crystal, who is serving life sentences at the Maine State Prison in Warren, cited the boy’s death and his frustration over how long the investigation was taking as a reason for his July 2015 rampage that left two dead and three others wounded.

Superior Court Justice William Anderson found on May 15, 2019, that although there was no testimony about how the baby’s skull was fractured, Mackin was responsible for his death because the defendant was the only person with him when the infant was stricken, according to a transcript of the proceeding.

Mackin took the stand at his jury-waived trial in April 2019 at the Penobscot Judicial Center in Bangor and denied hurting the child. Mackin said the baby just suddenly went limp.

In his appeal to the state Supreme Court, Mackin’s attorney, Stephen Smith of Augusta argued that the judge’s conclusion was wrong.

Justices, who held oral arguments remotely last month, disagreed.

“[Anderson] was amply justified in finding beyond a reasonable doubt that Mackin, acting with criminal negligence, caused the child’s death given [the] supported findings that the child’s death resulted from an inflicted injury and only Mackin could have inflicted it,” Acting Maine Supreme Judicial Court Chief Justice Andrew Mead wrote in his six-page opinion.