A man who was convicted of murdering his mother-in-law in Farmingdale in 2004 has lost another court appeal.

David Newall Grant, 60, formerly of Augusta, asked the U.S. Court of Appeals for the 1st Circuit to conclude that police violated his right to remain silent when they questioned him after he told them he didn’t want to talk.

A three-judge panel on Tuesday upheld earlier state and federal court rulings in the case.

Grant’s statements were introduced at trial over objections by his attorney, Christopher MacLean. Those statements have been the subject of several hearings. Tape recordings of the police questioning — with Grant’s voice hoarse from self-inflicted knife injuries — have been played in court.

A U.S. District Court judge ruled in September 2009 against Grant’s claim that his “statements were obtained in violation of his Fifth Amendment right against self-incrimination.”

But the judge allowed the ruling to be appealed on two questions, including “whether the Law Court erred in holding that Mr. Grant’s Miranda rights were scrupulously honored by police in accordance with” a 1975 U.S. Supreme Court ruling.

MacLean took those questions to the circuit court. Oral arguments were held in April at the University of Maine School of Law in Portland. The written decision was published Tuesday.

“I’m disappointed, but I believe the fight is worth fighting,” MacLean said Thursday. “They’re not supposed to be able to return and question the suspect again on the same thing after he invoked the right to remain silent. David repeatedly said he did not want to be questioned; he invoked his rights.”

MacLean said he plans to continue to try to get the ruling overturned, and is looking at filing a petition to determine whether the U.S. Supreme Court will review it.

“Each of the courts that have looked at this issue have agreed with the state’s position,” said Assistant Attorney General Donald Macomber, who represented the state in the appeals. “We’re confident that, if Mr. Grant takes this to the next level, that court will also agree with the state’s position.”

Grant is serving a 70-year prison term for killing Janet Hagerthy on Nov. 30, 2004. In imposing a sentence 10 years longer than prosecutors requested, Justice Nancy Mills called the killing “an example of extreme cruelty.”

Grant admitted to taking cocaine before going to Hagerthy’s home, where they argued over how to start a snowblower. Prosecutors said he beat, choked and stabbed the 74-year-old retired nurse and dumped her body in a field near her home.

Grant was later found in his pickup truck in a ditch near the Newport exit of Interstate 95, stabbing himself in the throat with a knife.