A planned protest of Bay Area Rapid Transit (BART) fizzled Thursday after officials reportedly cut cell phone services at some stations.

BART spokesman Linton Johnson told a KTVU reporter, who had noticed the disruption, that the public relations department had suggested that phone service be shut down.

Another BART spokesman, Jim Allison, reportedly admitted that the tactic had been "part of a larger strategy."

But Allison later claimed that he had been mistaken and phone service was not blocked.

"I haven't been able to find another incident in which this has happened," criminologist Casey Jordan told CNN's Suzanne Malveaux Friday. "I think perhaps it is unprecedented, and yet that's how these legal issues come to light and get debated. Whether it's legal or not it hasn't been tested in the courts. Public safety exceptions to or encroachments on our personal freedoms do happen."

"A lot of people are wondering, what happened to freedom of speech, assembly without government interference that's protected by the First Amendment?" Malveaux asked.

"They didn't try to shut down the protest. They simply turned off the cell service so it couldn't become viral," Jordan explained. "It really is just a cost/benefit analysis of where your freedom of speech begins to threaten the public safety."

The group No Justice, No BART had called for the protest following a string of killings by BART police.

"We are fighting for justice for Charles Hill, Oscar Grant, Fred Collins, Bruce Seward, Jerrold Hall, Robert Greer, and all victims of BART police violence and murder," the group said. "We demand that BART disband its murderous, inept, corrupt police department."

Watch this video from CNN's Newsroom, broadcast Aug. 12, 2011.

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