Raymond Lester enters Hancock County Superior Court in Ellsworth during his trial in November 2023. Gregory Rec/Portland Press Herald

A Portland man will remain in prison for the 2022 murder of his girlfriend at Acadia National Park after the state’s highest court denied appeals of his conviction and 48-year sentence.

Raymond Lester, 38, was found guilty in November 2023 of knowing or intentional murder in the death of 35-year-old Nicole Mokeme. A jury reached the verdict after several days of testimony and less than two hours of deliberation.

He was later sentenced to 48 years in prison after Mokeme’s family described Lester’s volatile history with Mokeme and their devastation at her death.

A jury found that Lester ran over Mokeme while the couple was attending a Black Excellence conference that Mokeme helped organize in June 2022.

After hitting Mokeme with his car late that night, Lester fled the park. He was arrested a month later after turning himself in at a Red Cross station in Cancun, Mexico, where he told police he had been robbed. They never found the car.

In Lester’s appeal, which the Maine Supreme Judicial Court heard in November, he argued that Superior Justice Robert Murray’s jury instructions “weighed too heavily in favor” of prosecutors.

The high court found no evidence of this in a ruling issued Tuesday. Rather, the justices wrote Murray’s instructions “complied with best practice.”

“They noted that the burden always remained on the state to prove all the elements of murder … beyond a reasonable doubt,” the court wrote. Murray’s instructions included a requirement that the state prove Lester was well aware his actions would result in Mokeme’s death.

Lester took specific issue in his appeal with the fact that his jury was not given a special instruction on whether his intoxication could have led him to recklessly, rather than intentionally, kill Mokeme. He argued the difference might have led jurors to instead find Lester guilty of a lesser “manslaughter” charge.

The high court found that while there was evidence at trial that Lester had been drinking before Mokeme’s body was found, “there was no evidence that Lester was drunk when he killed the victim.” In fact, Lester didn’t even argue this at trial. He focused instead on a lack of proof that he hit Mokeme at all.