Man accused of killing grand dad pleads the 5th

Nathan Carman turned accusations of murder around on his aunts during a court hearing scheduled to stop him from gaining a family inheritance by digging up information into two unsolved family deaths. 

Do you know what it is to plead the 5th?

His grandfather was murdered in 2013, and his mom, Linda Carman, disappeared during a boating trip in 2016. Nathan Carman, 23 was found and rescued after that trip eight days later.

And who did have motive to kill my grandfather?" Carman said in court Tuesday.

I'll say that some of the petitioners have awfully substantial motive, and I have very, very little.

His mother remains missing and is presumed dead. Three years earlier, Carman's grandfather, millionaire real estate developer John Chakalos, was found shot to death in his Connecticut home. Carman allegedly owned the same caliber rifle used in his grandfather's murder, and is a suspect in the cold-case investigation.

Carman's aunts believe that their nephew is responsible for both deaths, and that he was fueled by a potential $7 million inheritance.

Carman chose to invoke the Fifth Amendment during Tuesday's hearing when questioned about his gun and other financial documents that could provide clues about his role in his family members' deaths.

He refused to answer questions, he refused to take a polygraph exam, said Dan Small, an attorney representing the family.

That's not the conduct of someone who cares deeply about his grandfather and wants to find his grandfather's murderer.

Carman has fired his attorneys and is currently representing himself against the judge's advice. Judge David King said the family's attorneys may be allowed to depose Carman at some future date.

CBS news.