The Daily | December 10, 2012
By Michael Brick

The era of private conversations on city buses — and even on San Francisco’s iconic streetcars — may be coming to an end.  

Government officials are quietly installing sophisticated audio surveillance systems on public buses across the country to eavesdrop on passengers, according to documents obtained by The Daily. Plans to implement the technology are under way in cities from San Francisco to Hartford, Conn., and Eugene, Ore., to Columbus, Ohio.

Linked to video cameras already in wide use, the microphones will offer a formidable new tool for security and law enforcement. With the new systems, experts say, transit officials can effectively send an invisible police officer to transcribe the individual conversations of every passenger riding on a public bus.

But the deployment of the technology on buses raises urgent questions about the boundaries of legally protected privacy in public spaces, experts say, as transit officials — and perhaps law enforcement agencies given access to the systems — seem positioned to monitor audio communications without search warrants or court supervision.

“This is very shocking,” said Anita Allen, a privacy law expert at the University of Pennsylvania. “It’s a little beyond what we’re accustomed to. The adding of the audio seems more sensitive.”

In San Francisco, for example, transit officials recently approved a $5.9 million contract to install a new audio-enabled surveillance system on 357 buses and trolley cars over four years, with an option for 613 more vehicles. The contract, signed in July, specifies both modern buses and historic trolley cars.

A spokesman for the San Francisco Municipal Transportation Agency, Paul Rose, declined to comment on the surveillance program. But procurement documents explain the agency’s rationale.

“The purpose of this project is to replace the existing video surveillance systems in SFMTA’s fleet of revenue vehicles with a reliable and technologically advanced system to increase passenger safety and improve reliability and maintainability of the system,” officials wrote in contract documents.

In San Francisco, the Department of Homeland Security is funding the entire cost with a grant. Elsewhere, the federal government is also providing some financial support. Officials in Concord, N.C., for example, used part of a $1.2 million economic stimulus grant to install a combined audio and video surveillance system on public transit vehicles, records show.

The Lane Transit District in Eugene, Ore.; the Bay Area Transportation Authority in Traverse City, Mich.; the Central Ohio Transit Authority in Columbus; CT Transit in Hartford; and Athens Transit in Athens, Ga., have also been pursuing similar systems, documents show. The Maryland Transit Administration, which serves Baltimore, announced a bus recording system last month. The agency started recording audio on 10 public buses, with plans to expand the system to 340 more. Each bus uses six cameras. A recorder stores 30 days of data, the Baltimore Sun reported.

Some transit officials say the systems merely provide a useful way to resolve complaints from passengers. “From my standpoint, the use of audio is a lifesaver for the drivers,” said Joel Gardner, executive director of Ozark Regional Transit in Arkansas. “We can review audio and negate these false accusations.”

But surveillance technology experts say the audio systems can easily be used for other purposes.

“Given the resolution claims, it would be trivial to couple this system to something like facial or auditory recognition systems to allow identification of travelers,” said Ashkan Soltani, an independent security consultant asked by The Daily to review the specs of an audio surveillance system marketed to transit agencies. “This technology is sadly indicative of a trend in increased surveillance by commercial and law enforcement entities, under the guise of improved safety.”

Searching for audio surveillance gear, some transit officials make clear their desire for fly-on-the-wall powers. In Eugene, Ore., for example, transit officials demanded microphones capable of distilling clear conversations from the background noise of other voices, wind, traffic, windshields wipers and engines. Requesting a minimum of five audio channels spread across each bus, they added, “each audio channel shall be paired with one or more camera images and recorded synchronously with the video for simultaneous playback.”

Numerous private companies are seeking to gain a foothold in the market for customized audio systems in public buses. Safety Vision, a company based in Houston, offers the RoadRecorder 7000, the hub of a high-definition video system built to store 128 gigabytes of data collected from 12 cameras, each with its own embedded microphone. DTI Group, an Australian company scheduled to exhibit its wares at the 2014 American Public Transit Association Expo, promotes its specialty as the ability to merge audio recordings with video and tracking data.

While video surveillance has become ubiquitous, taken for granted everywhere from retail stores to public streets, experts say the courts have generally applied stricter standards to monitoring verbal communications.

In Maryland, where officials openly described audio surveillance as a tool of law enforcement, officials have enacted their system over significant resistance. The local transit agency took the first step in 2009, asking the state attorney general whether an audio recording system would violate wiretapping laws.

For the next three years, the transit agency pursued legislation to authorize the audio surveillance. Civil liberties groups testified that the system would violate wiretapping laws and basic constitutional protections against unlawful search and seizure.

“An audio device on an MTA vehicle will pick up all passenger conversations, whether uttered softly or shouted,” Melissa Goemann, legislative director of the state chapter of the ACLU, said in written testimony at a committee hearing in March.

Though a legislative committee rejected the bill, the transit agency proceeded with its plan. In an advisory letter, the state attorney general’s office told the agency that signs warning passengers of the surveillance would help the system withstand a court challenge.

Privacy law experts said the audio surveillance systems alone mark a significant advance in surveillance. But connected to existing data from ticketing machines, global positioning systems, speech recognition software and face recognition software, the microphones raise intriguing new possibilities.

“It’s one thing to post cops, it’s quite another to say we will have police officers in every seat next to you, listening to everything you say,” said Neil Richards, a professor at Washington University School of Law. With the microphones, he said, “you have a policeman in every seat with a photographic memory who can spit back everything that was said.”