Former Harvard law professor Alan Dershowitz explained why the president and people more generally shouldn’t talk directly with the FBI when they’re being investigated on Hannity Tuesday night.

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“That is even if you say something that is absolutely the truth and you pass a lie detector test and you get some sleazy flip witness who has been threatened with his family going to jail unless he composes or sings, nonetheless, you can be charged with lying if they have one witness who contradicts what you said,” Dershowitz continued. “That’s why people don’t go and speak to prosecutors, ask Martha Stewart.”

The conversation centered on the new development, that Special counsel Robert Mueller will accept written answers from President Donald Trump. (RELATED: Report: Mueller Will Accept Written Answers From Trump About Russian Collusion)

Dershowitz continued, “If you want to cooperate with the FBI, do it through your lawyer. Do not speak to them directly. Tell your lawyer what you think. Then your lawyer can honestly relate what you told him to the FBI. That avoids any possible —,” when asked what the appropriate way to interact with the FBI would be.

“We shouldn’t have a statute like 10o1 that makes it a crime for anybody to lie to the FBI. You should have to swear under oath on a Bible before you can be charged with perjury,” he added.

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