California State Sen. Mark Leno will introduce a bill today that requires smartphone manufacturers to install a “kill-switch” on devices to help prevent thefts. Leno, who represents the tech-haven of San Francisco, said in a statement last month that smartphone thefts were becoming “one of the top catalysts for street crime in many California cities.”

Leno, along with San Francisco District Attorney George Gascon, had previously urged smartphone manufacturers to voluntarily install the kill-switch. That apparent deadline has passed, and now Leno’s bill will be introduced in the California Legislature.

It has quickly garnered support of Bay Area political heavyweights, including Oakland Mayor Jean Quan and Assemblymember Nancy Skinner of Berkeley. Supporters will be alongside Leno as he rolls out the bill in San Francisco.

“We cannot continue to ignore our ability to utilize existing technology to stop cellphone thieves in their tracks,” Leno stated. “It is time to act on this serious public safety threat to our communities.”

The cities of New York and San Francisco have long been lobbying for the kill-switch as smartphone robberies have increased by as much as 12 percent in some metropolitan areas. In 2012, FCC Chairman Julius Genachowski reported to Congress that almost 40 percent of all robberies in New York and Los Angeles involved smartphones, and that smartphone crime had increased 54 percent in Washington, D.C.

While the top two smartphone manufacturers (Samsung and Apple) have embraced the idea of a kill-switch for their products, wireless carriers such as Sprint, AT&T, T-Mobile and Verizon have nixed the proposal, claiming it would allow hackers to easily hijack smartphones.

If passed, this legislation would likely be eventually phased in nationwide, as California represents the largest consumer market in the country.