A federal judge dismissed a lawsuit filed against Facebook, Google and Twitter by families of patrons killed in the 2016 Orlando nightclub massacre.

In his ruling Friday, U.S. District Judge David Lawson found no legal merit for the case filed in December 2016 in Detroit by the families of Tevin Crosby, Juan Ramon Guerrero Jr., Javier Jorge-Reyes and others. They claimed gunman Omar Mateen was radicalized by propaganda found through social media.

“There are many conclusions that can be drawn from the facts alleged in the amended complaint about the ethics and moral responsibility of those maintaining social media sites, including the defendants,” Lawson wrote. “But because the plaintiffs have not pleaded facts that plausibly establish legal claims for which relief can be granted, the court will grant the motion and dismiss the case.”

Lawson concluded the complaint offered no facts suggesting the videos and other messages “had anything at all directly to do with the shooting, other than that the principles espoused in them motivated Mateen to carry out the dreadful act.” During the June 2016 rampage that killed 49 at Pulse nightclub, Mateen pledged allegiance to the Islamic State group in telephone conversations with a 911 operator and a police negotiator. He was killed in a shootout with SWAT team members after a three-hour standoff.

A similar lawsuit against Twitter was dismissed in 2016 and affirmed two months ago by a federal appeals court. In that case, a federal judge in San Francisco agreed with Twitter that the company cannot be held liable because federal law protects service providers that merely offer platforms for speech, without creating the speech itself.

Lawson said the judges in that case were “confronting strikingly similar allegations” and found no “causal connection” between Twitter accounts and a terrorist attack. In his ruling, Lawson wrote that plaintiffs similarly failed to show that defendants “engaged in conduct subjecting them to liability for Mateen's terrorist act.”

“Although certain organizations, most notably banks, occasionally have been found liable under these federal statutes for aiding international terrorists … there is not a single case in which social media providers have been held responsible,” he wrote. “And in several other cases, attempts to make out such a case have failed.”

Jeff Karoub reports for the Associated Press.