Addressing concerns raised when it shut down all wireless communications, the San Francisco area’s Bay Area Rapid Transit (BART) board of directors has decided to set down in writing when it is appropriate to block cell phone use in its stations.

On Thursday, the BART board approved a policy saying it would only turn off wireless communications in the face of “extraordinary circumstances.” Such circumstances include evidence that cell phones are being used as “instrumentalities in explosives,” to facilitate criminal activity such as the taking of hostages, or to facilitate plans that would destroy property or “substantially disrupt public transit services.”

BART got a lot of bad press over its August decision to block cell phone signals to avoid a potential protest. The American Civil Liberties Union and the Electronic Frontier Foundation both took the agency to task for its decision, saying that it was an unacceptable breach of the First Amendment. A later report from security researcher Chris Soghoian found that the shutdown of cellphone and WiFi service in the stations was accomplished with two e-mails to BART’s service providers, raising even more concerns about the ease with which communications could be limited.

The BART spokesman who took credit for the idea, Linton Johnson, was reassigned following the backlash, CBS’s San Francisco affiliate reported. The agency told the station that the move was not intended to be punitive.

BART sought input from the Federal Communications Commission and the ACLU before approving its policy Thursday, the Contra Costa Times reported. The FCC suggested wording for the BART policy that emphasized that the agency must weigh whether the public safety risks were worth shutting down service.

In an interview with the paper, ACLU attorney Linda Lye did not endorse the policy, but said that it was a good step. “You don’t shut down free speech before it happens,” Lye told the paper. “I think this was a teaching moment.”

FCC Julius Genachowski said in a news release that BART had taken an “important step” in responding to the concerns raised by its actions over the summer, but said that the FCC will be reviewing the issue of when it’s appropriate to disrupt cell service.

“For interruption of communications service to be permissible or advisable, it must clear a high substantive and procedural bar,” he said.

He said that the FCC will continue to examine laws and policies that deal with service interruptions and will announce and “open, public process” to let the public comment on those issues.

When do you think it’s appropriate to shut down cell communications?

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