According to a nine-page internal report released this week, the cameras also have reduced the number of allegations left unresolved due to lack of evidence, helped exonerate more officers accused of misconduct and increased the percentage of allegations deemed false.
The report compared misconduct allegations and instances where force was used in 2013, before officers began wearing cameras, to 2016, when nearly all had begun wearing them.
By April, the department plans to complete upgrading each of its nearly 1,200 body-worn cameras to newer models with superior video quality and the ability to store two minutes of images before an officer hits "record," instead of the current 30 seconds.
The report said overall misconduct allegations were down 43.1% when 2016 is compared with 2013. More serious allegations related to criminal behavior, discrimination, force and racial or ethnic slurs were down 47.4%, while allegations related to conduct, courtesy, procedure and service were down 40.4%.
Use of force by officers was found to be on the rise overall, climbing 14% since 2013. But high-level use of force — such as physical take-downs or employing Tasers, chemical agents or weapons — was down 16.4%. Low-level use of force, such as physical strength, controlled holds and Taser warnings, was up 25.3%.
Police Chief Shelley Zimmerman said the statistics were evidence that body-worn cameras discourage violence.
"This data is consistent with feedback received from officers indicating body worn cameras help de-escalate some situations, and results in the use of lesser controlling force to gain compliance without the need for greater controlling/defending force," she wrote in the report.
Brian Marvel, president of the labor union representing San Diego police officers, said he was not convinced by the statistics showing use of force has increased overall.
"I think you're seeing more thorough report writing and much better documentation of the force that was used," he said, suggesting some uses of force had been going unreported because officers couldn't watch a video of themselves in action. "Prior to body-worn cameras, you got into an altercation and you were having to recall everything."
Marvel said another factor could be a significant increase in recent years in the number of incidents with people who are mentally ill, which often require the use of force.
Marvel said he was particularly pleased to see the reduction in the use of high-level force, which he said means less instances of injuries to officers and the people they are trying to take into custody.
"It'd be great if everybody would just fully cooperate, but in the real world that's not going to happen," he said.
Zimmerman stressed in her report that use of force, while on the rise statistically, is still rare.
Of 520,000 incidents that San Diego officers responded to in 2016, just over 4,600 — less than 1% — involved the use of force.
But it's still a problem that overall use of force is on the rise, said Rev. Shane Harris, president of National Action Network San Diego and a frequent critic of the department.
"Excessive force has gone down, but use of force is up still and it's climbing. And it's our belief they should be held accountable for each equally," Harris said. "Just because excessive force is down, it doesn't mean use of force is justified."
Harris said that although the other numbers in the report are good news, city leaders still have work to do.
"They shouldn't be complimenting themselves all the time and patting themselves on the back," he said. "They need to constantly fight to make police relations better in the city of San Diego."
Garrick writes for the San Diego Union-Tribune