PROVIDENCE, R.I. (CBS/AP) — A civil trial underway in Providence will determine whether insurance companies should cover Nathan Carman‘s $85,000 claim for his boat that sank off New England in 2016.

Insurers are refusing to pay the claim, saying Carman made suspicious alterations to the 31-foot vessel before leaving Rhode Island with his mother on a fishing trip.

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Carman, who lives in Vermont, was found eight days later in a life raft near Martha’s Vineyard. Linda Carman is presumed dead.

Nathan Carman outside Concord District Court (WBZ-TV)

The federal judge hearing the non-jury trial that began on Tuesday says testimony will be limited to questions surrounding the insurance claim.

Lawyers for the insurance company said one of the altercations Carman made right before setting out was drilling holes right above the water line and not properly patching them.

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They also called the boat’s prior owner, Brian Woods to testify that the Chicken Pox was seaworthy when he retrofitted and sold it to Carman.

Carman’s lawyers said Woods took advantage of his lack of experience and sold him a defective boat.

Nathan Carman, who has denied doing anything to make the boat unseaworthy, has also been named a “person of interest” in the 2013 shooting death of his 87-year-old grandfather in Connecticut.

He has been accused by his aunts of killing his grandfather and possibly his mother in order to collect inheritance money.

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