Members of the Black Lives Matter movement and other pro-black activists have been on edge since it was revealed that the FBI has created a new category of domestic terrorists: "black identity extremists."

According to a Mother Jones report, BLM activists in New York have a reason to worry about being watched. The Rockland County chapter of the Black Lives Matter Global Network has filed a lawsuit claiming that the police department of upstate New York town Clarkstown unlawfully spied on their members for at least a year. 

The documents, provided to Mother Jones by attorney William O. Wagstaff III, also allege that police racially profiled members and violated their free speech and assembly rights.

The documents also show that the department's Strategic Intelligence Unit surveyed the local BLM group using a "geofence" —  a method of tracking and analyzing social media posts used by ad firms — to watch the Twitter and Instagram feeds of BLM members.

The local DA's office discovered that the police were spying on BLM members and instructed the department to stop. The police department continued its surveillance anyway.

Peter Modafferi, former chief detective for the Rockland County DA’s office, caught Sergeant Stephen Cole-Hatchard, former head of Clarkstown’s Strategic Intelligence Unit, disobeying his orders to stop spying on BLM members, and addressed him in an email submitted to the court.

“Steve,” wrote Modafferi in the email, “I mentioned before, you really should not have Black Lives Matter listed as a target of surveillance.”

Although the case has some precedent — activist group We The People sued the Clarkstown police department for illegal surveillance earlier this year and won a $300,000 settlement — ACLU attorney Chris Conley notes that social media surveillance is a legal grey area.

“You are collecting lots of information that is publicly available — is that a problem?” Conley said. “If I can look at one tweet, why can’t I suck them all up? The question still hasn’t been fully answered.”

The ALCU lawyer added, “I don’t think there would be any question that an officer sitting at a laptop and going to Twitter and digging around on things would be constitutional. The question is, does it change when it goes from individual manual investigations to bulk surveillance?”

Things change with geofencing Conley said because “basically, police would be able to investigate the people who are running the protest and the people who are participating, keep a file on them, and keep tabs on who’s involved — and that’s not what police are supposed to be doing."

The suit alleges that the local police did more than watch online activity. It claims that the department also placed snipers on roofs around BLM protests.

Susan Freiwald, a professor at the University of San Francisco Law School, said that no such surveillance should be conducted unless there is a legitimate concern of criminal wrongdoing. 

“The intention is to illegally surveil people with the hope that they can silence them,” Wagstaff said.

BLM is seeking an unspecified amount of monetary damages and a cease-and-desist order by the court against Clarkstown’s Strategic Intelligence Unit.