Police in California do not need a warrant before using surveillance drones, after Democratic governor Jerry Brown vetoed a bill to that affect.
While the proposal, AB 1327, successfully passed both houses of the state's legislature last month, Brown decided to block the measure.
"There are undoubtedly circumstances where a warrant is appropriate. The bill's exceptions, however, appear to be too narrow and could impose requirements beyond what is required by either the 4th Amendment or the privacy provisions in the California Constitution," he wrote in a letter to the California State Assembly.
While the bill did cover other government organisation, its principle focus was ensuring that the police obtained warrants before deploying surveillance drones. The only exceptions listed by the proposal were emergency situations such as fires, environmental disasters and search and rescue operations.
The bill had also gained support from a number of privacy advocates who feel that the unrestricted use of surveillance drones is too invasive. Police have long used helicopters for surveillance, but drones are capable of flying quietly at lower attitudes and are often equipped with sophisticated camera equipment.
The Republican Assemblyman Jeff Gorrell, who originally introduced the bill, expressed his disappointment with the decision.
"We live in an era of government surveillance, where powerful government agencies like the NSA and IRS have demonstrated blatant disregard for Americans' privacy rights. In Congress, I will make personal privacy a top priority and work on establishing common sense drone restrictions that California failed to establish."
The regulations regarding the use of drones are often complicated and differ from country to country. Currently there are six US state that require police officials to obtain warrants before using drone surveillance.