A personal injury lawyer filed a federal lawsuit on Friday, claiming that Black Lives Matter and its leaders are responsible for the wounding of a police officer by a lone shooter after protests in Baton Rouge one year ago.

The lawsuit names five front-runners of the movement as defendants, including Alicia Garza and Johnetta “Netta” Elzie, but fixates on social media posts and television interviews by Deray Mckesson as evidence that they support and cause violence. It’s asking for $75,000 on behalf of an unnamed officer who was shot three times and permanently disabled during an attack that also killed three police officers on July 17.

Gavin Long, the shooter who was killed by police that day, was an ex-Marine from Kansas City, thought to be seeking revenge after two white officers shot and killed 37-year-old Alton Sterling, a black man. Louisiana State Police detectives recently stated that Long had not joined in any of the protests in Baton Rouge or elsewhere, according to local reports.

But Sterling was killed on July 5, and the bulk of the 28-page filing claims that protests often led by Mckesson that weekend and beforehand were what caused Long to ambush police more than a week later.

Citing what Black Lives Matter referred to as a “Weekend of Rage,” it details protesters throwing rocks and getting arrested, claiming that Mckesson was “inciting lawless actions … and did nothing to stop the criminal conduct.”

“DeRay McKesson was present during the protests and he did nothing to calm the crowd and, instead, he incited the violence on behalf of [Black Lives Matter],” the filing states.

But the connection is unclear. While the suit lists several protests since the movement started around 2012 to rail against killings of black people, including at the hands of white police, it does not point to any time defendants explicitly encouraged a shooting.

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A First Amendment lawyer described the case as “bizarre” to the NewsHour, saying it looks more like a fishing expedition than a legitimate claim.

David Roland, the director of litigation at the Freedom Center of Missouri, also said that is “extremely unsettling.”

“I think the lawsuit first and foremost was intended to be a shot across the bow to anyone who has been publicly critical of police,” said Roland. “It’s saying, ‘Unless you expressly disavow tactics that we don’t like, we’re going to come after you, we’re going to destroy you in court.’”

Roland likened the motivation behind the suit to the Ironclad Oath, which during the Civil War would only allow certain employment rights to people who took an oath disowning the Confederacy.

“If you did not explicitly disavow the actions of the Confederates, then you violated the oath and were ineligible to work,” he said. “It’s actually the same principle being applied here.”

This is at least the third lawsuit to follow the protests in Baton Rouge after Sterling’s death.

Mckesson and other activist leaders have since settled one with Baton Rouge that claims the arrests that weekend were unreasonable and unconstitutionally vague, violating their civil rights.

And Donna Grodner, the lead lawyer in the suit filed Friday who said she was unauthorized to discuss the case, is also involved in another case against Black Lives Matter and Mckesson on behalf of an officer who was hit by debris during the protest.

Though that suit, filed in November, does not directly accuse Mckesson of throwing anything, it says he arrived to Baton Rouge with the intention to “incite others to violence against police.”

In March, Mckesson’s attorney, William Gibbens, asked the U.S. district court judge to dismiss the case for relying too heavily on speculative allegations. The request was denied. Local media reported that the judge said a key question is “whether, under Louisiana law, Black Lives Matter is capable of suing and being sued,” a decision that he has yet to make.

But apart from that legal question, Roland was more worried about damage to freedom of speech. While suggesting that the suit filed Friday would be thrown out because it failed to make a connection between the activists and the shooting of an officer, he also pointed out the burden of proof is lesser in civil cases than in criminal.

“It’s easier to dissuade protests, to chill speech, using the threat of a civil suit at least in some ways,” he said. “It can’t result in someone going to jail, but it can result in them being bankrupt.”

Mckesson was active on Twitter but had not mentioned anything about the suit as of Saturday afternoon.

Omar Etman contributed reporting.