Last year between January and November, thieves broke into some 28,000 cars, up 26 percent over the same period in 2016.
Under an oddly framed state law, not all can be prosecuted as felonies.
District Attorney George Gascon explains. "Common sense would say if you see broken glass next to your car, that means somebody broke into your car," Gascon said.
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Not so, according to the law.
If your doors are locked and someone breaks the window and steals something, that's a felony car burglary.
But, if your doors are unlocked and someone breaks the window - that's a simple misdemeanor theft - a big difference.
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Car burglary is a felony and it carries more significant consequences than a car theft would.
So, Gascon wants the law changed through a bill State Senator Scott Weiner and two San Francisco Assembly members are proposing.
SFDA Gascon sponsoring bill to make felony prosecutions of carbreakins,now epidemic, easier by changing an oddly worded state law. pic.twitter.com/dQU1ct8TJo— Vic Lee (@vicleeabc7) January 23, 2018
"Under the law that we're proposing, if you break the glass even though your vehicle was unlocked, it would be a felony," Gascon said.
And it's difficult proving in court that a car was locked under the existing law, which is a big reason most of the break-ins occur in tourist areas like Fisherman's Wharf.
"We have to prove in order to have a car burglary is that actually the vehicle was locked," said Gascon.
And that is challenging for prosecutors. Tourists visit and leave.
"The tourist is gone and can't testify that the door is locked," said Sen. Scott Weiner.
If the bill passes that won't be necessary.