Black Lives Matter leader DeRay Mckesson, seen here in 2016, and four others are being sued by an unidentified Baton Rouge police officer for allegedly inciting and encouraging violence at demonstrations. (Max Becherer/AP)

One year after law enforcement officers in Texas and Louisiana were ambushed by angry gunmen who said they were retaliating for high profile fatal police shootings nationwide, critics of Black Lives Matter are still trying to pin responsibility on the movement.

In a new lawsuit filed Friday in Louisiana, an unidentified Baton Rouge officer blamed DeRay Mckesson, Johnetta “Netta” Elzie and three other prominent Black Lives Matter leaders for allegedly inciting and encouraging violence at demonstrations across the country.

More specifically, it claims the movement and rhetoric of its leaders inspired a decorated former U.S. Marine sergeant to unleash a torrent of bullets upon Baton Rouge police on July 17, 2016, leaving three officers dead and another three injured — including the plaintiff, identified only as Officer John Doe Smith in the lawsuit.

The officer, a 42-year-old father of two who worked in law enforcement for 18 years, was left “permanently disabled” when bullets struck his abdomen, shoulder and head during the methodical ambush by 29-year-old Gavin Long at a convenience store.

Long, who was black and was killed by police in a shootout, had written in a suicide note that his actions were a “necessary evil” intended to “create substantial change within America’s police force.” He said he felt compelled to “bring the same destruction that bad cops continue to inflict upon my people, upon bad cops as well as good cops in hopes that the good cops (which are the majority) will be able to stand together to enact justice and punishment against bad cops.”

The phrase Black Lives Matter first received national attention in summer 2014 and, since then, has become part of conversations on race in America. Here's how the phrase became a movement. (Claritza Jimenez,Julio Negron/The Washington Post)

The attack came 12 days after a different shooting in the same city, when a white Baton Rouge police officer shot and killed Alton Sterling, a 37-year-old black man, outside a convenience store. A day later, another black man, Philando Castile, was fatally shot during a traffic stop by a police officer in Falcon Heights, Minn.

Black Lives Matter protests erupted across the country, including a peaceful one July 7, 2016, in downtown Dallas. But it turned deadly, too, when an Army veteran named Micah Johnson ambushed law enforcement officers who were overseeing the demonstration route. Five Dallas officers were killed and seven more were wounded.

Before he was killed in a standoff with police, Johnson told negotiators he was angry over the shootings that week in Louisiana and Minnesota and wanted to kill white police officers.

Ten days after Dallas, Long drove to Baton Rouge from Kansas City, Mo., and continued the bloodshed on a Sunday morning.

The new Baton Rouge lawsuit claims that Long’s ambush attack may not have happened if Black Lives Matter leaders had not incited violence among their followers, even though an exhaustive investigative report determined that Long had not attended any of the Black Lives Matter demonstrations in Baton Rouge after Sterling’s death and that he believed protests were a waste of time.

Mckesson and his fellow activists were responsible for the unidentified officer’s injuries because they incited “disdain, hatred and violence against police” at protests, on social media and in news interviews, according to the lawsuit. It says Black Lives Matter “seized upon” the fatal police shooting of  Sterling by a Baton Rouge police officer “to further incite its followers to take action against police.”

Local news outlets reported that the description of the officer’s injuries match those of East Baton Rouge sheriff’s deputy Nick Tullier, who nearly died in the shooting and remains hospitalized at a rehabilitation facility in Houston.

The officer has endured more than 16 abdominal surgeries and suffered extensive brain damage that has affected his communication abilities, according to the lawsuit. He is still under constant threat of infection in his remaining wounds.

“While there is no way to know how far (the officer) will progress back to normal life, he is definitely permanently disabled,” the lawsuit says.

The complaint asks for at least $75,000 in damages.

“This is quite a world,” Mckesson told the Associated Press Friday when the publication made him aware of the lawsuit. He later told CNN that he was “confident” the lawsuit “has no merit.” Elzie declined to comment to CNN, the publication reported.

This lawsuit is the second one filed against Mckesson by a Baton Rouge police officer; both were filed by attorney Donna Grodner. In the previous lawsuit, Grodner argued on behalf of another unnamed officer that Black Lives Matter and Mckesson were responsible for injuries the officer sustained during protests that took place in Baton Rouge after Sterling’s death.

Mckesson’s attorney asked a federal judge to throw out that lawsuit, reported the Advocate, arguing that Black Lives Matter is a social movement, not an organization, and therefore cannot be sued. The judge has not yet decided whether to dismiss the case, according to the Advocate.

Mckesson and other protesters arrested during that July demonstration in Baton Rouge later sued the city and local law enforcement agencies. They later agreed to settled, reported the Advocate. Charges were never brought against 98 of the 190 people arrested at the protests, including Mckesson.

On Sunday, another lawsuit was filed against Baton Rouge and Louisiana law enforcement agencies on behalf of 13 protesters and two reporters arrested during the demonstrations, alleging excessive use of force and civil rights violations, reported BuzzFeed News.

David Roland, director of litigation at the Freedom Center of Missouri, told PBS News Hour that he was concerned that civil lawsuits blaming Black Lives Matter and its leaders for the actions of individuals loosely affiliated — if affiliated at all — with the movement could threaten the First Amendment.

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

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