ROCKLAND, Maine — Justices with the state’s highest court listened Tuesday afternoon to arguments concerning whether the 2012 conviction of a 38-year-old Rockland man for murder should be overturned.

Defense attorney Jeremy Pratt also argued that the 45-year sentence imposed on his client, Arnold Diana, was excessive.

The state prosecutor, however, countered that there were no errors by the trial judge that call for either an overturning of the verdict or a reduction in Diana’s sentence.

Diana was convicted of strangling ex-girlfriend Katrina Windred on Nov. 20, 2010, at his apartment at the Thorndike complex on Main Street in Rockland. Testimony and evidence provided during the jury trial indicated that Diana strangled the 47-year-old Friendship woman while her 10-year-old son was waiting outside in her car.

Justice Jeffrey Hjelm imposed a 45-year sentence on Diana in October 2012.

Pratt argued before the Maine Supreme Judicial Court on Tuesday that the first search of Diana’s apartment was invalid because deputies did not have any belief that a crime had been committed. Assistant Attorney General Donald Macomber told the justices, however, that the search was legitimate since police were investigating a missing person case, Windred had said she was going to Diana’s, and Diana was on probation.

Pratt also said that the trial judge erred by double counting the impact on the child when he determined the sentence.

There is no timetable for when the court will issue its decisions on the appeals, but during Tuesday’s hearing, one justice said that his initial reaction concerning the sentence was that it was too lenient. Another justice said the impact on the child is and will be devastating.

Diana did not testify during his trial. Also, a confession Diana made to police was ruled inadmissible and not heard by the jury because Maine State Police investigators continued to question him after he said he wanted it to stop.

Nevertheless, in July 2012, the jury of seven men and five women found him guilty of murdering Windred.

Windred had stopped by Diana’s apartment to drop off some groceries prior to Thanksgiving. The prosecution said Diana killed Windred because the two had broken up, and he realized she had met another man.

Diana told police that after he strangled Windred, he got the boy from the car, told him his mother was taking a nap, and put him in the same bedroom where Windred’s body lay. As the boy later slept, Diana wrapped Windred in a blanket and drove to Thompson Meadow Road, where he dumped her body on the side of the road. A man walking his dog there found her body three days later. The boy was brought to the child’s father the following morning.