It's been a little over a year since the Mountain View Police Department outfitted all of its officers with wearable cameras, joining a growing number of Bay Area law enforcement agencies aiming to boost accountability, assist in criminal prosecutions and create an impartial record of police activity to discipline or exonerate officers following complaints from the public.

While it's hard to say whether the new cameras have reduced complaints against officers or changed the way people interact with law enforcement in Mountain View -- two big selling points for the program -- it's clear that the cameras are here to stay. The Mountain View Police Department is expected to buy up a new line of body cameras early next year to improve officer-worn camera footage, and will revise the policies governing how cameras are used and data is stored.

An overwhelming number of city police departments in the nine Bay Area counties have adopted police body camera programs over the last two years, including the Mountain View Police Department, following promising results from studies linking body camera programs with a precipitous drop in use of force and formal complaints against officers. What's more, the adoption came soon after the height of riots and protests following the shooting death of 18-year-old Michael Brown by a police officer in Ferguson, Missouri, which triggered a nation-wide call for greater police accountability.

One year into the program, the body cameras don't appear to have changed much in in the way Mountain View officers interact with the public. Six complaints have been filed against officers over the last year, and the only time body camera footage was used was to refute claims made by an individual to exonerate an officer, according to police spokeswoman Katie Nelson.

"Because we expect such a high level of customer service representation from our officer to begin with, their behavior in the field hasn't changed much," Nelson said.

Instead, most of the complaints come from people who misunderstood the law or violation they were charged with, and the complaint has nothing to do with alleged officer misconduct or criminal wrong-doing, said Lt. Dan Frohlich of the Mountain View Police Department.

"A majority of the complaints are people who don't understand why they got stopped and ticketed," Frohlich said. "Most people don't know that the cameras are even on."

The Mountain View Police Department launched its body cam program in September last year, putting down $135,000 to equip 66 officers with the cameras and pay for uploading data and storage costs. Cameras are rolling whenever police are out on patrol and interacting with the public, meaning over 400 gigabytes of data is recorded each month. At the last count, the policy department was sitting on close to 5.8 terabytes of video footage.

Although complaints against officers hasn't dropped to zero, Frohlich maintains that the program has been a useful tool that officers use almost every day. Officers in the field can use a playback tool on the camera for writing police reports in the car, and footage can later be sent to the Santa Clara County District Attorney's Office as evidence in criminal prosecutions.

In order to boost the effectiveness of the body cam program, Frohlich said the department is looking to buy a new set of camera that will be much better at recording incidents and showing what transpired from the officer's point of view. The department currently uses what's called Axon Flex, a camera model shaped like a small cylinder that attaches to a lapel mount or a pair of specially-designed sunglasses.

Frohlich said the model was supposed to give an accurate account of what an officers sees, but it came with a fair number of problems. The cord attaching the camera to the battery supply would get in the way, would frequently break and would need to be replaced as often as twice a month in some cases. The camera itself is loose and gets bumped around easily, Frohlich said, and during the early stages of the program, officers would come back with poorly-aimed footage of things like the sky or the ground.

One of the perks of the camera model is that the Axon Flex is that it includes "pre-event recording" and shows 30 seconds of footage prior to the officer turning on the camera. That means if an officer is unable to turn on their camera in time to show a suspect committing a crime, it's still recorded in the 30 seconds of silent video.

"By the time you've hit the button, you've already missed the violation," Frohlich said.

This helpful perk was the cause of some mishaps early in the program as well. On multiple occasions, officers would turn on their cameras within 30 seconds of using the restroom, unintentionally catching footage of them washing their hands, or worse, Frohlich said.

The new model the department is planning to buy is the Axon Body camera, which is a box-shaped camera that rests on the chest of officers and catches a wide 130-degree angle view and should eliminate all of the problems officers had with the Axon Flex, Frohlich said.

The department is also considering taking advantage of Bluetooth technology where cameras automatically switch on when an officer turns on the police car lights, eliminating the chance that the officer might forget to turn on the camera. Turning on one officer's camera can also trigger every other policy body cam in the area to turn on as well.

Earlier this year, the Leadership Conference on Civil and Human Rights, working with the consultant firm Upturn, created a "policy scorecard" designed to critique just how transparent and accountable body camera policies are amongst law enforcement agencies across the country. Each department was judged by seven categories, including officer review, personal privacy, footage retention and footage misuse. While the Mountain View Police Department wasn't included in the study, it would have scored well in some areas and poorly in others.

In regard to protecting footage from tampering and misuse, the department would have likely satisfied all of the report's criteria. The policy only allows officers to access footage in the database through authorized computers and devices inside the department headquarters, and only on a "need to know" basis for completing criminal investigations, preparing official reports or preparing for a "judicial process." The database keeps a log of anyone who views camera footage, which includes the location from which it was viewed.

The department also has explicit guidelines for when officers must record incidents, and when they have discretion to turn off the camera for sensitive interactions, including interviews with victims -- both positive measures, according to the scorecard.

Where things get troublesome for most Bay Area police departments is how long to hang onto camera footage before deleting it. The San Jose Police Department policy, for example, states that it retains body-worn camera footage "for a period of time," but fails to define what that means and never explicitly says the footage will be deleted at the end of that period.

The Mountain View Police Department has guidelines that are a little more clear: footage is deleted after one year, unless the case is picked up by the Santa Clara County District Attorney and needs to be retained until the case is adjudicated. The policy scorecard report criticized departments with retention policies going beyond six months, but Frohlich said the grace period plays an important role in hanging onto data for pre-trail court proceedings.

"The problem is you lose data for discovery," Frohlich said. "Some of these cases get put on the backburner for quite a while."

The other trouble spot is that none of the police department policies that the report analyzed had a "blanket limitation" that bars officers from reviewing camera footage prior to filing an incident report, and Mountain View is no exception. Allowing officers to review footage before filing a report is contrary to investigative best practices and opens up the possibility for police to lie in a way that isn't contradicted by the footage, compromising the credibility of officer statements and the integrity of investigations, according to policy analysts at the American Civil Liberties Union.

Mountain View officers are actually encouraged to review footage in the field and file reports from their car, which Frohlich said allows police to spend "more time on their beats and less time here at the station." There are limits to this, however. The department policy states that any personnel involved in an officer-involved shooting is required to provide an initial statement to investigators prior to reviewing any recorded footage.