In 1967, the California Supreme Court ruled that a city couldn't prohibit nondisruptive political activity inside a railroad station.

That was before cellular phones were invented and before the first BART train rolled down the tracks. But it's a precedent the transit agency may have to confront as it defends its decision to cut off cell service at the site of an expected trackside protest last Thursday, and its long-standing ban on "expressive activities" inside the fare gates.

BART says it might pull the plug on phone service again this afternoon to counter plans for a 5 p.m. demonstration at Civic Center Station in San Francisco, where a transit police officer fatally shot a knife-wielding man July 3.

The legality of such a decision may soon arrive in court.

"This is new territory in the United States," said Gene Pilicinski, executive director of the First Amendment Center at Vanderbilt University. Although courts haven't addressed a government cell phone shut-off, he said, "historically we have kept our hands off free expression. ... The government has a very high ladder to climb."

Safety issues

By cutting off an entire mode of communication, "you're shutting down much more speech than could possibly be related to a protest," said Michael Risher, an American Civil Liberties Union lawyer. If BART is concerned about passenger safety, he said, its focus should be to "prevent the violence, not the speech."

BART said that's just what it was doing by temporarily interrupting cell phone service at downtown stations Thursday after getting reports that organizers planned to use mobile phones to coordinate a demonstration over the same police shooting. A similar protest at Civic Center a month earlier had disrupted the afternoon commute.

The transit agency cited its rules, in effect for many years, that forbid all assemblies, demonstrations or "other expressive activities" inside the fare gates. Demonstrations are allowed outside the gates with a permit, which must be obtained a week in advance.

"The paid areas are for people getting on and off trains," BART spokesman Jim Allison said. "Allowing a free rein of activities in that area would present an unreasonable danger."

Some legal analysts said the rules, as written, seem overbroad.

"A big protest is a demonstration, but so too is a T-shirt" with a political message, said Vikram Amar, a UC Davis law professor.

'Absurdly overreaching'

BART could legally enforce its rules if they were limited to gatherings that would be dangerous on a station platform, said University of Michigan Law Professor Leonard Niehoff. Even so, he said, the agency is "absurdly overreaching" by prohibiting potential demonstrators from communicating by cell phone.

But Marvin Ammori, a University of Nebraska law professor, said in a blog posting that BART's action - which he described as a "terrible idea" - might pass legal muster if courts judged it a "content-neutral" measure to promote public safety.

BART's first day of service in 1972 was nearly five years after the last time California's high court considered a government ban on political activity at train stations.

The court overturned the arrests of antiwar leafletters inside Union Station in Los Angeles. It ruled 5-2 that the city could limit the size of political gatherings in such locations and keep them away from congested areas, but could not prohibit them altogether without violating the First Amendment.