Monday on Fox News Channel’s “Fox & Friends,” Harvard law professor Alan Dershowitz batted down the merit of obstruction of justice charges aimed at President Donald Trump for what he said was exercising his constitutional power and authority regarding the firing of then-FBI Director James Comey and instructing the Department of Justice what to and not to investigate.

“If Congress were to ever charge him with obstruction of justice for exercising his constitutional authority under Article 2, we’d have a constitutional crisis,” he explained. “You cannot charge a president with obstruction of justice for exercising his constitutional power to fire Comey and his constitutional authority to tell the Justice Department who to investigate, who not to investigate. That’s what Thomas Jefferson did. That’s what Lincoln did. That’s what Roosevelt did. We have precedents that clearly establish that.”

“When George Bush, the first, pardoned Caspar Weinberger in order to end the investigation that would have led to him,” Dershowitz continued. “Nobody suggested obstruction of justice. For obstruction by the president, you need clearly illegal acts. With Nixon — hush money paid, telling people to lie, destroying evidence. Even with Clinton, they said that he tried to influence potential witnesses not to tell the truth. But there’s never been a case in history where a president has been charged with obstruction of justice for merely exercising his constitutional authority. That would cause a constitutional crisis in the United States.”

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