The San Francisco Police Department’s recent strategy to reassign dozens of officers to neighborhood foot beats has contributed to a significant decline in thefts and assaults, a new study released Wednesday found.

The report by UC Berkeley’s Goldman School of Public Policy found that daily incidents in San Francisco of larceny theft — which include vehicle break-ins — dropped nearly 17 percent, and assaults dropped 19 percent in the months after Chief Bill Scott reassigned 69 officers to foot patrols on Sept. 1, 2017.

The strategy nearly doubled the number of officers walking neighborhood beats. Many are deployed to property crime hot spots that include tourist attractions where out-of-town visitors time and again fall victim to teams of stealthy thieves.

“It’s good news. It’s not surprising though,” Deputy Chief Ann Mannix said of the study’s findings. “If we continue to educate the public and target the hot spots, hopefully we can continue to lower property crimes and the violent crimes as well.”

The decision to shake up police staffing was an early test for Scott, who started in January 2017 after being hired from the Los Angeles Police Department, where he served as a deputy chief. San Francisco was, and continues to be, in the throes of a troubling auto-burglary epidemic that hit an all-time high last year with more than 31,000 reported incidents.

Vehicle break-ins have begun to trend downward this year compared with the same period last year, dropping 16 percent in the first 10 months, but incidents remain at near-record levels.

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The UC Berkeley study — done in conjunction with the California Policy Lab — comes as the Police Department continues to increase foot patrols. The department last month announced it would add 10 officers, two sergeants and a lieutenant to walk the gritty stretch of Market Street between Fourth and Eighth streets that is plagued by open-air drug use and aggressive street behavior.

In their study, UC Berkeley researchers Maura Lievano and Steven Raphael measured the drop in thefts and assaults by looking at a four-month period before and after Sept. 1, 2017, while controlling for other variables not related to the shift in staffing.

For larceny theft, which is how the Police Department categorizes crimes like shoplifting and car break-ins, the researchers saw a drop by nearly 22 incidents a day, or a 16.9 percent decrease.

Assault incidents, meanwhile, dropped by around 7.5 incidents a day, or around 19.1 percent.

The study, though, found that the additional foot patrols didn’t impact the city’s other most-frequently reported crime categories, including robbery, burglary, drug offenses, fraud, larceny, vandalism and vehicle theft.

It’s also unclear if the impacts to larceny theft and assault were short-lived because the study measured only the change in crime for two months into the policy change.

Scott’s decision to reassign the nearly 70 officers to foot patrols came with a cost to other specialized crime-fighting units. To come up with the staff, the chief disbanded the department’s auto burglary task force, an 18-person unit that had netted more than 200 arrests since it began in 2015.

But while the unit was seeing some results, vehicle break-ins are notoriously difficult to solve, and police in San Francisco typically make arrests in just under 2 percent of cases. In 2017, that number dipped to 1.6 percent.

The shift from focusing on specialized units to uniformed foot patrols is part of the department’s increased focus on what is called “proactive policing” versus “reactive policing.”

Rather than devoting so many resources to catching criminals, proactive policing seeks to prevent some crimes — particularly quality of life and crimes of opportunity — from happening in the first place. Striking the right balance between the different assignments is a challenge faced by law enforcement jurisdictions around the country.

“The special crime units are generally plainclothes and they wait for a crime to occur and try to react to that,” Mannix said. “What the uniform patrol is doing is trying to stop a crime before it even happens. In the long run, it seems to make more sense.”

The number of auto break-ins began to sharply increase in San Francisco starting around 2010. From 2003 to 2010, the number of larceny thefts hovered around 2,100 incidents a month, but over the past seven years, the study found, monthly incidents nearly doubled to more than 4,000.

Coinciding with the rise in thefts from 2010 to 2017 was a rapidly changing San Francisco, which saw its population increase by almost 10 percent, employment up 38 percent and typical weekday exits from BART stations up 20 percent over that period, the study found.

What’s more, San Francisco has experienced “a pronounced increase” in tourist visits during the time period, Lievano and Raphael wrote.

Tourists are prime targets for auto burglars because they may have vehicles with valuables and luggage and may not be aware of the magnitude of the city’s epidemic. San Francisco has mounted an expansive public awareness campaign — including posting warning signs around the city — to educate visitors about the break-in problem.

Evan Sernoffsky is a San Francisco Chronicle staff writer. Email: esernoffsky@sfchronicle.com Twitter: @EvanSernoffsky