Drone technology was put to the test against privacy in a California court recently – and the drones lost.

In Northern California’s Sonoma County, changes are coming to a controversial drone code enforcement program, after the county’s land use planning and development permitting agency, Permit Sonoma, agreed last week to settle a lawsuit for allegedly spying on much more than what the program initially intended.

Permit Sonoma agreed to the settlement brokered by the American Civil Liberties Union (ACLU) of Northern California, after three local residents sued the agency and a number of county officials last year over the use of invasive drone surveillance.

Permit Sonoma’s drone program was started in 2019 to allegedly target illicit cannabis operations.

However, ACLU attorney Nick Hidalgo says it quickly spread to more mundane issues.

The lawyer said the code enforcement officers had been using low-flying drones to monitor and record people’s homes, fenced-in yards, swimming pools and hot tubs, mostly without their knowledge.

They then used the footage as evidence to target people for a wide array of code violations that have resulted in millions of dollars in excessive fines.

“So not only were these drones being used to violate people’s right to privacy, but they were doing so without any clear idea of what they were looking for,” said Hidalgo.

“And in a lot of cases they of course found code violations because no one’s perfect.”

The ACLU the filed a lawsuit in June on behalf of three residents, arguing that the drone initiative launched in 2019 was now over-extending its reach, to target unpermitted cannabis grows in hard-to-access rural areas had gotten out of control, trampling residents' right to privacy in their homes.

“Forty years ago, the California Supreme Court said that aerial surveillance of a person’s home violated our Constitutional rights, and that was with an airplane flying at 1600 feet using a magnification lens that had a maximum zoom of 4 times,” the union said in a statement.

Hidalgo says the surveillance landscape now is very different.

“Drones today, including the ones in Sonoma and purchased by many other agencies around the state, can fly lower than 100 feet, can fly quietly, sneak up on people, peer through windows, have zoom capabilities between 56x and 200x, can be equipped with thermal imagery.”

The three plaintiffs in the case had been cited for civil code violations spotted during drone flights.

As a result of the settlement, Permit Sonoma must now notify residents if their home has been surveilled with a drone.

“The county also agreed to stop stockpiling images of people's homes. Drone footage will now be deleted 30 days after images are collected, unless it is part of an investigation, in which case it will be deleted 30 days after the investigation closes.

“The county also agreed not to share images of a home or its surrounding areas with third parties unless required to do so by law.

“In addition, the county must put several transparency measures in place to make sure residents understand how the government uses drones. That includes presenting a revised drone use policy to the Board of Supervisors for public comment and producing drone flight logs to the ACLU for two years.”

A spokesperson for Permit Sonoma says the agency disagrees with the ACLU’s characterisation of the case; pointing out that the settlement was, in fact, not an admission of fact and says Sonoma County has successfully defended the use of drones on previous occasions.

The spokesperson said the agency was settling to avoid an expensive legal process.

As part of the settlement, the three residents will each receive $50,000 and Hidalgo says Permit Sonoma will change how the agency uses drones, including obtaining a warrant or a resident’s consent.

They are also agreeing to not only publish their drone policy, which they had not done prior, but also revising it through a public process, which will involve a meeting with the board of supervisors – a meeting that Sonoma County residents are welcome to attend and voice their concerns if they have any.