We have this thing called the Fifth Amendment to the U.S. Constitution that allows people to refuse to testify in any of the proceedings described here in this article.
Martha Stewart wouldn't have spent two second in prison if she had simply kept her mouth shut.
Not necessarily true. They wanted to imprison her and they would have just found something else. They NEEDED her to get the blame for 'insider trading' to keep the public's attention away from the fact that THEY were doing ILLEGAL INSIDER TRADING. After they convicted her, they changed the laws so that politicians can do INSIDER TRADING LEGALLY. Not you, not anyone else, but THEY CAN.