Democrat lawmakers have strongly criticized President Trump for firing FBI Director James Comey, likening it to Watergate and calling for a special prosecutor to take over the investigation into alleged collusion between the Trump campaign and Russia during the presidential election.

Rep. Sean Patrick Maloney (D-NY) joined Tucker Carlson tonight to discuss how Democrats have reacted to Comey's firing.

Tucker said many Democrats - like Massachusetts Sen. Elizabeth Warren - may claim to know that Comey was fired because Trump was worried about the Russia investigation, but they don't actually know that.

"Why are you saying crap like that that you don't know if it's true?" Tucker asked. "That's totally irresponsible. Like, why would you say something like that?"

Maloney said he's no fan of Comey, but he does find it concerning that Trump would fire the person that's leading an investigation into his campaign and associates.

"That is unprecedented in American history," Maloney said. "No president has ever fired an FBI director for that reason."

Tucker pushed back, pointing out that there's no proof that Trump fired Comey "for that reason."

"I would remind that you're an elected official with the responsibility to say things you can prove and that are true," Tucker said. "And you're violating that responsibility because you don't know why he got fired."

Watch more above.

WATCH: CNN's Cooper Rolls Eyes at Conway During Interview on Comey

Russian Media Invited Into Trump's Closed-Door Meeting With Kremlin Officials

Students Stage Walkout After MN City Council Votes to Disband Local Police

Mainstream Media Accuses Trump of Abuse of Power, Fascism for Comey Firing