Harvard law professor Alan Dershowitz condemned FBI agent Peter Strzok for texting his mistress about stopping the Trump presidency during a Sunday interview.

WATCH:

Dershowitz told Maria Bartiromo on “Sunday Morning Futures” that FBI agents are allowed to have partisan proclivities but that he “draw[s] the line” at FBI agents expressing a desire to influence an investigation.

The inspector general report that came out this week revealed a new text message from Strzok to his colleague and lover Lisa Page promising “we’ll stop” Trump from becoming president. (RELATED: STRZOK: ‘We’ll Stop’ Trump Presidency)

“FBI agents are allowed to be biased. They’re allowed to support political candidates, that’s part of the law,” Dershowitz said. “Where I draw the line is when an FBI agent says, ‘we’ll stop him.'”

“That’s not an expression of bias; that’s not saying who we’re gonna vote for. That sends a message to the American people that the Federal Bureau of Investigation is going to interfere in an election in an effort to try to stop the election of one candidate rather than the other,” he said. “That to me was where the red line was crossed.”

Dershowitz also asserted that this text message precludes Strzok from continuing to be an FBI agent.

Julia Ainsley, an NBC News national security and justice reporter, similarly argued on Thursday that this particular text message is “damaging” because it shows an “influence in the investigations.” (RELATED: MSNBC Admits New Strzok Texts Are Damaging)

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