While the SFPD continues its deployment of officer-worn body-cameras, the Oakland Police Department has had them for some time. Since 2009, to be precise. However, according to the Chronicle, that roughly seven-year headstart doesn't mean OPD has the system down pat. In fact, a recent murder trial has reveled that the department accidentally deleted 25 percent of all the footage collected since the program began.

Oops.

“Nothing should have ever been lost from the system,” OPD Sergeant Dave Burk explained in court. “The settings were set to never delete.” And yet, deleted the footage was.

Officials claim that in 2014 technicians were updating the police department's computer system — which includes the body camera footage archive — when an employee checked a box "preserve" instead of another box "preserve everything." This simple slip up was enough to erase a huge swath of recorded evidence. The mistake was caught a month later, and metadata was used to determine the amount of footage lost.

Oakland police were quick to insist that no cases had been impacted — anything that had specifically been marked as "evidence" was stored elsewhere — and yet this mass deletion only came to light because a defense attorney for a man charged in the 2013 killing of 66-year-old Judy Salamon had requested police body camera footage, only to be told it no longer existed.

This deletion goes to show that equipping officers with body cameras isn't enough to guarantee that the evidence collected by them will be around when defendants need it. As with all things, the technology has to be properly maintained for it to fulfill its intended purpose — a realization which OPD is no doubt belatedly coming to.

Related: Oakland Police Department's Radios Keep Failing (Like, All Of Them At Once)