George Zimmerman is suing Democratic presidential candidates Pete Buttigieg and Elizabeth Warren for defamation over tweets they posted about Zimmerman’s killing of unarmed black teenager Trayvon Martin. His lawsuit accuses them of “maliciously publishing false and misleading” tweets in order to “garner votes in the black community.”

Zimmerman filed the lawsuit Tuesday in Florida, seeking $265 million “for loss of good will and reputation” and financial damages.

In 2012, Zimmerman the two candidates lagging in support among African American voters.

But CBSN legal contributor Keir Dougall, a former federal prosecutor and trial lawyer, says Zimmerman would face an “uphill climb” trying to prove his case in court.

Because Zimmerman is a public figure, to win his claim he “would have to prove that the statements were knowingly false or reckless to the truth,” Dougall explained. That’s a high bar. And at the same time, the First Amendment offers a great deal of protection to Warren and Buttigieg to exercise their right to free speech.

“One of the core types of speech the First Amendment protects is political speech, and you’ve got two presidential candidates tweeting in their campaigns — that’s obviously political speech,” Dougall said. “The First Amendment would be at its strongest in protecting this particular type of speech.”

In 2014, a Florida judge threw out a libel suit Zimmerman filed against a news organization on the grounds that he was a public figure and could not prove the outlet acted with reckless disregard for the truth.

CBS News has reached out to the Buttigieg and Warren campaigns for comment and will update this story if they provide responses.

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