Police fatally shot six people in San Francisco last year, but you wouldn't know that from looking at Open Justice, a website created at the behest of California Attorney General Kamala Harris to which state law enforcement agencies are legally required to submit information. And San Francisco isn't alone: California's official tally of those killed by police in 2015 is missing more than 50 shootings according to a study from Texas State University covered by the Chronicle.

Assistant professor of criminal justice Scott Bowman, the study's co-author, compared media reports and police news releases to the official tally. “We don’t believe there’s some plot to withhold evidence or withhold a narrative,” he told the Chronicle. “The data that’s collected now is better than no data, but it’s a far cry from being useful data.”

From 2006 to 2015 there were 439 fatal police shootings in California that were not reported to the Department of Justice, the study suggests. The Los Angeles County Sheriff's department did not report 34 killings during that period and the Los Angeles Police Department did not report 21. Fresno was near the top of the list of non-reporting areas with 24 police killings, and San Francisco, in addition to the 6 from 2015, did not report two other police killings over the period.

"Nobody has any idea how many police shootings there are," Stanford Law School professor Robert Weisberg told the Chronicle. “Any scrutiny is good, and if this causes more scrutiny, that’s good, and if it causes any embarrassment, that’s fine.” Weisberg, who is also co-director of the Stanford Criminal Justice Center, added that “It’s tough to motivate police departments to engage in their own self-criticism if they’re allowed to be in denial about how frequent these incidents are."

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