Washington (CNN) President Donald Trump has derided the Fifth Amendment as the refuge of mobsters, and during Watergate President Richard Nixon infamously told aides, "I want you all to stonewall it, let them plead the Fifth Amendment, cover up, or anything else."

Despite the negative implications of taking the Fifth, the US Supreme Court has long regarded the right against self-incrimination as a venerable part of the Constitution and tried to ensure that a witness' silence not be equated with guilt.

In a possible switch in sentiment, Trump may end up taking the Fifth, his lawyer Rudy Giuliani suggested on Sunday.

As he responded to questions about special counsel Robert Mueller's Russia investigation, Giuliani declined to rule out Trump invoking his right against self-incrimination. Giuliani also said Trump wants to testify and that "every lawyer in America thinks he would be a fool to testify."

On a separate legal issue, Giuliani said Trump could resist a subpoena to testify -- an assertion that conflicts with Supreme Court precedent. Mueller has reportedly raised the possibility of subpoenaing Trump as part of his investigation into any Trump campaign connection to Russia's interference in the 2016 election.

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