The Maine Supreme Judicial Court will hear oral arguments Thursday in the appeal of 73-year-old Merrill Kimball, who was convicted last year of murder in the 2013 shooting of Leon Kelley at a bee farm in North Yarmouth.

Kimball’s attorneys contend that the trial judge, Justice Roland Cole, made several mistakes during Kimball’s trial in the Cumberland County Courthouse in Portland last April.

Kimball, a Yarmouth lobsterman, had been so confident in his claim of self-defense that he had rejected a plea offer to a lesser charge of manslaughter.

Cole acknowledged on June 5, when he sentenced Kimball to 25 years in prison, that “my hands are tied” when he imposed the mandatory minimum sentence for the crime of murder.

Kimball’s attorneys, Daniel Lilley and Cheryl Richardson, contend in written filings for the appeal that the trial judge failed to adequately instruct the jury. They also say the judge erred in allowing testimony that Kimball had been drinking alcohol on the day of the shooting because no one said he seemed impaired. The attorneys further contend that the judge improperly ruled to exclude evidence that Kelley’s wife, Kathleen Kelley, had been upset with Kimball’s wife, Karen Thurlow-Kimball, over inheritance of the bee farm business.

Since the shooting on Oct. 6, 2013, Kimball has maintained that he acted in self-defense when he shot the 63-year-old Kelley three times at Brown’s Bee Farm after Kelley assaulted him and kept coming at him.

A jury rejected Kimball’s self-defense argument and convicted Kimball of murder rather than the lesser charge of manslaughter.

The shooting followed a confrontation between the family of Kelley, whose father-in-law, Stan Brown, owned the farm; and the family of Kimball, whose wife, Karen Thurlow-Kimball, managed the bee farming business for Brown.

The animosity between the families started after Brown, who was 95 when he died last year, had Thurlow-Kimball run the bee operation and made her a beneficiary to inherit the business and some of his land.

The fate of Brown’s estate is now pending in Cumberland County Probate Court, where Kathleen Kelley filed a petition to become representative for the estate last Nov. 18.

“Mr. Brown did not have a will that any of his daughters could find,” said attorney Charles Hedrick, who represents Kathleen Kelley in the probate case.

Hedrick said that Kathleen Kelley has been appointed special administrator to the estate and that he expects the case to be resolved after several more filings. The probate case was somewhat complicated because Brown had three daughters, as well as grandchildren and great-grandchildren of his deceased children, who are also heirs, he said.

Kimball’s attorneys argue Cole made a mistake by not instructing the jury that it could find that Kimball had been adequately provoked by Kelley, who was 6-foot-4 and 285 pounds, after being repeatedly struck as he retreated away from Kelley.

“The evidence shows that Leon Kelley started the confrontation: he ‘got into Kimball’s face,’ he first assaulted Kimball by physically pushing him hard four or five times,” Lilley and Richardson wrote. “It would be reasonable for a jury in this case to find that a sudden and violent attack on Kimball and his family members was sufficient to cause Kimball to react with extreme anger or extreme fear which influenced his actions.”

Lilley and Richardson wrote that the judge should have given the alternate instruction to the jury because a prosecutor said in closing arguments that Kimball acted out of extreme anger.

Assistant Attorney General Donald Macomber countered that the Maine Supreme Judicial Court should reject that argument because Kimball’s attorneys had already asked that the jury be instructed on Kimball’s self-defense claim and had already been deliberating the case when Lilley asked the judge for a different jury instruction.

“Under these circumstances, the trial court correctly refused Kimball’s belated request for an adequate provocation manslaughter instruction because the evidence did not generate one and because it would have been confusing to the jury in light of the self-defense instruction that was given on the previous day,” Macomber said in his written brief for the appeal.

Kimball is seeking to have his convicted vacated or to be granted a new trial.