PROVIDENCE, R.I. (WPRI) — A civil trial involving a Vermont man whose mother disappeared after their boat sank during a fishing trip in 2016 began Tuesday morning in federal court in Providence.

Nathan Carman, 24, is being sued over an $85,000 insurance claim he made on the vessel. The National Liability and Fire Insurance Company and BoatUS argue they shouldn’t have to pay up, saying Carman significantly altered the boat’s condition and caused it to sink.

In their opening statement, the plaintiffs said: “this is a case about a boat that left Ram Point Marina with holes in it.”

After setting out from South Kingstown, Nathan and Linda Carman’s boat went down in the vicinity of Block Canyon. The pair was missing for eight days until Nathan was found unharmed and brought back to shore by the U.S. Coast Guard. Linda was never found and has been presumed dead.

The defense is seeking to prove the vessel was old and had issues before Carman bought it.

The defense also claims the insurance policy was changed multiple times based on the known facts of the case.

The first person called to testify was Brian Woods, who sold Carman the boat just 10 months before it sank. He said the vessel was in great condition at the time after years spent working on it.

The judge is giving each side 15 hours to present their case and he’s using a chess clock to keep track. There’s also no jury in the trial, so the judge will be the deciding factor.

Carman is listed as a witness for both sides but it’s unclear whether he’ll be called to testify. He sat in silence on Tuesday, only shaking his head in disapproval at times.

Carman and his attorney declined to comment outside court.

The trial will focus solely on the insurance aspect of the case. The judge has barred any testimony and questions regarding Linda Carman’s disappearance as well as the still-unsolved shooting death of her millionaire father John Chakalos.

Chakalos was found dead in his Connecticut home in 2013.

While Nathan was considered a “person of interest” in his grandfather’s death, he hasn’t been charged in either case and denies his involvement.

His aunts—Linda’s sisters—believe Nathan killed both his mother and his grandfather in hopes of inheriting a portion of Chakalos’ $44 million estate.