Sgt. Ryan Crosby of the Bayview Station tests out an Axon body camera during training for use of the devices at Ingleside Station in San Francisco on Sept. 1, 2016. (Jessica Christian/2016 S.F. Examiner)

Inconsistent audio on SFPD body cameras prompts transparency concerns

In early May, when a Texas man attacked an employee at a downtown Subway restaurant with a knife, one of the two San Francisco police officers who responded stopped the assault by fatally shooting the attacker.

The incident was the second time a police shooting in San Francisco was captured on an officer’s body-worn camera, but not all of it was recorded. Officer Kenneth Cha, who killed 26-year-old Nicholas Flusche, only recorded a portion of the incident because his body camera was not activated until after he fired his weapon.

The video recording, which lasts one minute and 19 seconds, is silent for the first 30 seconds. This designed gap in the audio of body-camera footage is now raising concerns among some of the people who were involved in creating the policy for the cameras about the accuracy of what is recorded. The concerns center on if and when officers decide to turn off their cameras and the use of a mute button on the device.

The May 3 shooting at the Subway at 940 Market St. has raised renewed worries about how well body cameras are working as a tool of transparency.

“Given all the body-worn camera cases I have, where there is no sound or where the body-worn camera is turned on, [it’s] only [in] time for the clean-up. I think that the department general order needs to be clearer,” said Deputy Public Defender Rebecca Young, who worked closely with the San Francisco Police Department to develop its policy.

While the department policy does not specifically mention muting audio, SFPD brass has approved the practice by applying the policy’s rules around video, which requires that officers justify why they stopped recording. Meanwhile, the device’s manufacturer said no such issues have been raised by their many clients across the country and world.

Still, the importance of the mute button has not gone unnoticed by the San Francisco Police Officers Association, which recently asked Chief William Scott about the matter to make sure it remains an option for officers.

According to the minutes of the POA’s May 17 meeting with Scott, the union was guaranteed the mute function will not be removed.

“President [Martin] Halloran discussed the mute function feature on the body worn camera,” reads the minutes of the meeting in the June issue of the POA Journal. “President Halloran stated he met with Assistant Chief [Hector] Sainez and Deputy Chief [Robert] Moser who agreed to allow this function to remain an option for officers. Officers will have to document in their reports why they muted their cameras during a recording. The department will be forwarding a draft DB [draft bulletin] to address the use of the ‘mute’ function. Until then, there is no change to the current DGO [department general orders].”

Nathan Ballard, speaking on behalf of the POA, said the organization has the same position on the use of the mute button as the department.

The department, which fully equipped more than 2,000 officers with cameras earlier this year, introduced the cameras to increase transparency and help rebuild public trust after a litany of scandals in recent years. But when it comes to the mute button, the SFPD did not acknowledge any issues around a lack of transparency or any troubles with a less-than-clear policy on audio recording.

“Officers who deactivate recording prior to the conclusion of an incident (audio or video) are required to document the reason for doing so in either CAD [computer assisted dispatch], the police report, a statement or memorandum,” said SFPD spokesperson Sgt. Michael Andraychak in a statement.

He added that there are good reasons for turning off the audio and video.

“There may be times in the course of an incident or investigation in which it is necessary to stop recording (audio or video) for the purposes of discussing sensitive tactical or law enforcement information or required to deactivate recording such as in a hospital setting or where the BWC would inhibit information gathering,” he wrote.

The department did not respond to a question about how often officers have chosen to mute the sound on their body cameras or whether unwarranted muting is seen as an issue. The department also declined to provide a draft bulletin addressing audio, which it told the POA was in works.

Sgt. Ryan Crosby of the Bayview Station tests out an Axon body camera during training for use of the devices at Ingleside Station in San Francisco on Sept. 1, 2016. (Jessica Christian/2016 S.F. Examiner)


The importance of the combination of audio and video from a body-worn camera was illustrated in the case of Sean Moore, according to his lawyer, Deputy Public Defender Brian Pearlman.

Moore, 43, was shot by Officer Cha — the same officer who shot Flusche — on Jan. 6 after Cha and his partner, Officer Colin Patino, got into a scuffle with Moore on his doorstep in the Oceanview neighborhood. The incident, which was caught on both officers’ body cameras, was the first police shooting to be recorded on the devices in San Francisco.

The combination of audio and video in the recording were key in exonerating Moore for any wrongdoing, Pearlman said. In fact, the officers’ reports directly contradicted the audio of the incident, he said.

Specifically, the officers said in their interviews after the shooting that Moore charged at them, forcing Patino to use his baton. But in the body-camera footage, Moore was seen running away from the officers.

“If you just saw them going up and down the stairs, and then this happened, the cops could have said anything was said or anything had happened,” said Pearlman, who added this an increasingly common issue in court cases. “They seem to shut [the audio] off at very crucial times.”

On May 10, a judge dropped the charges alleging Moore had attacked Cha and Patino.

According to Axon, manufacturer of SFPD’s body-worn cameras, the “Function” button on the Axon Body 2 Camera can be used to pair the device, to mute the device or to add markers to the video as it is recorded. (Graphic courtesy Axon)


According to Axon, the manufacturer of the body-worn cameras, the mute button was created in the new model used by SFPD — the Axon Body 2 — after a number of customers requested the option.

“In terms of adding it, it was requested from many of the clients,” said Steve Tuttle, an Axon spokesperson. The mute option is only available on two current models: the Axon Body 2 and Axon Flex.

All cameras come with the mute function off, said Tuttle, who added that a department has to consciously activate the mute function. The mute option was first available in September 2015.

The body camera’s mute option is used by some police departments in states where the law require two-party consent (like California) before an audio recording can begin, according to Tuttle. In other cases, it’s used by law enforcement agencies that want to mute audio when personal information, like social security numbers or criminal backgrounds, are mentioned in an interview.

Tuttle has not heard about any issues around the use of the option, which isn’t referred to as a “mute button” in the manual. There, it’s called a “Function” button that can mute sound as well as mark specific sections of the video.

But Tuttle did note that officers likely would not mistakenly press the button. “It’s a press-and-hold for three seconds [maneuver],” he said.

The first 30 seconds of Officer Cha’s body-camera camera footage that lacked audio during the shooting at Subway was not due to use of the mute button, but rather the buffering that occurs each time an officer activates a camera.

Tuttle said the buffer mode, which was implemented at the behest of police departments and unions, is designed to prevent officers from recording discussions not related to an incident and those that may be private or embarrassing.

Axon body cameras rest in a charging station at Ingleside Police Station. The 30-second buffering mode when the camera is activated and the optional mute button have raised questions about the devices’ effectiveness when recording audio. (Jessica Christian/2016 S.F. Examiner)


Deputy Public Defender Young said these audio issues should have been more at center stage in the body-camera policy working group because the absence of audio can mean missing evidence in a case.

It can also be used as a loophole for officers wanting to hide what occurred in a misconduct case, she said.

“We should revisit the DGO, particularly around the issue of the individual officer’s discretion,” she said. “The sound is turned off a lot.”

Paul Henderson, another member of the policy working group who participated as a representative of Mayor Ed Lee, said he doesn’t recall any mention of audio.

“I don’t recall ever talking about that or even knowing at the time we were building the policy that was an option,” said Henderson, now the interim director of the Department of Police Accountability, about the audio mute option.

Julius Turman, the president of the San Francisco Police Commission, did not return a request for comment.

While muting was not discussed when the body-worn camera policy was being created, the option can be activated or deactivated by the department if the policy calls for it, Tuttle said.

“Policy would have to dictate when that is allowed,” said Tuttle, who added that the function must be turned on by the system administrator.

“If the agency has decided not to have anybody use that [button], they can have the cameras remain in that mode to allow the [mute] not to work,” Tuttle said.

Audio aside, the problem of activation and reporting deactivation is already an issue with body cameras.

“The departmental guidelines specify that the camera should be on, including volume, anytime they are conducting a witness interview, victim interview, detention of a defendant, [or] arrest of a defendant,” Young said. “However, the DGO on the body-worn cameras is not followed by the police officers on the street. The officers frequently don’t have the camera turned on.”

The issue does not seem to have come up on the radar of prosecutors.

“The implications are concerning if it’s being used in a manner that undermines the fair administration of justice, but I’m unaware of any cases where the use of the mute button was problematic,” said Max Szabo, a District Attorney’s Office spokesperson.

Meanwhile, it remains unclear how, or if, the Police Commission will address the policy around the mute button. Crime

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Officer Kyle Wren of the Bayview Station models a body camera after talking about his experiences with the device at Ingleside Police Station in San Francisco on Sept. 1, 2016. (Jessica Christian/2016 S.F. Examiner)

Axon body cameras rest in a charging station at Ingleside Police Station. The 30-second buffering mode when the camera is activated and the optional mute button have raised questions about the devices’ effectiveness when recording audio. (Jessica Christian/2016 S.F. Examiner)

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