Murdaugh murders: Alex Murdaugh's attorneys say investigators manipulated, destroyed evidence

SOUTH CAROLINA -- Lawyers for Alex Murdaugh, a South Carolina attorney accused of killing his wife and son, now say a key piece of evidence at the center of the state's case can't be trusted.

They're accusing investigators of manipulating and destroying evidence.

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Authorities said Murdaugh killed his wife, Maggie, and son, Paul, at the family's home in June of last year. At the center of this case is an allegedly blood spattered t-shirt that authorities said puts Murdaugh at the scene of the crime when it happened. But Murdaugh's team questioned that evidence in a filing this week.

"A big part of the prosecution's case is that he fired a weapon, killing his wife and his son, and that with the firing weapon, that blood of the deceased actually splattered on his shirt," said civil rights Attorney Areva Martin.

Murdaugh's team showcased photos showing what they said is a chemically damaged, cut up and stained shirt, writing state investigators elected to conduct its tests in a manner that would prevent anyone else from conducting subsequent tests.

The filing went on to claim the state's own expert didn't initially find spatter, but instead changed his findings after pressure from investigators.

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Murdaugh's lawyers said the state needs blood spatter evidence because it is exceedingly difficult to explain how he could have murdered Paul with multiple 12-gauge shotgun blasts at pointblank range in a small closet without getting at least some blood spattered on his shirt.

Murdaugh's team asked for the communications between the state and that expert.

"I think the judge is going to want solid, logical answers from the prosecutors before they allow their expert to give testimony," Martin said.