Santa Clara County enacted a pioneering spy-tech law aimed at protecting the public’s right to privacy.

Under the ordinance passed by the Board of Supervisors earlier this week, agencies that want to acquire new surveillance technologies must first craft policies on how they would use them.

Advocates hailed the regulatory framework as “future-proof” for applying not only to existing tools such as drones, license plate readers and cellphone trackers, but also emerging technologies. Violating the new law will be a misdemeanor.

Supervisor Joe Simitian began pushing for the new law two years ago amid concerns about agencies buying snooping gear without telling the public.

The San Jose Police Department quietly bought a drone for its bomb squad, later apologizing for doing so without an open discussion. Up in Oakland, police faced fierce criticism for creating a so-called Domain Awareness Center to spy on residents.

An effort by this county’s Sheriff’s Office to buy a “Stingray” cellphone tracker came to a halt after Simitian demanded more information about how it works and how it would be used.

The new oversight measure met with some resistance from county law enforcement and the District Attorney’s Office, but won unanimous support from county supervisors.

“The technology is not, per se, the issue,” said Simitian. “It’s the wisdom with which we use it. I’m hoping we’ll make wiser, more fully informed decisions going forward, and that the public will now have a voice in those discussions.”

From now on, agencies planning to buy new spy-wear must first analyze its privacy and due process implications. They must draft a policy outlining the planned use. They will also have to come back with yearly reports about how and how often they actually deployed it.

“Simply put, we’ll be asking these important civil liberties questions before, rather than after, we acquire some new technology,” Simitian said. “We’ll have policies in place before we acquire some new technology. And we’ll be holding ourselves accountable on a regular basis.”

The idea is to force government agencies to consider whether the benefits of using the surveillance technology outweigh the financial costs and the impact to peoples’ privacy and civil liberties.

“I firmly believe we can both protect the public, and respect the public’s privacy and due process rights,” Simitian said. “In fact, I believe we’re obligated to do both.”

More than two-dozen community groups and civil rights organizations signed a letter endorsing the policy.

"The new ordinance will ensure a transparent and fair process, with an opportunity for public input, to decide whether to adopt new surveillance technologies,” said Adam Schwartz, an attorney for the Electronic Frontier Foundation. “This will promote trust between the police and the community.”