The California Assembly has passed a bill that would require law enforcement agencies to obtain a warrant before using a surveillance drone as part of a criminal investigation. The bill specifically states:

(a) A public agency shall not use an unmanned aircraft system, or contract for the use of an unmanned aircraft system, except as provided in this title. This title shall apply to all public and private entities when contracting with a public agency for the use of an unmanned aircraft system. (b) A law enforcement agency may use an unmanned aircraft system if it has obtained a warrant based on probable cause pursuant to this code. (c) (1) A law enforcement agency, without obtaining a warrant, may use an unmanned aircraft system in emergency situations if there is an imminent threat to life or of great bodily harm, including, but not limited to, fires, hostage crises, "hot pursuit" situations if reasonably necessary to prevent harm to law enforcement officers or others, and search and rescue operations on land or water. (2) A law enforcement agency, without obtaining a warrant, may use an unmanned aircraft system to assess the necessity of first responders in situations relating to traffic accidents, and to inspect state parks and wilderness areas for illegal vegetation, vegetation or fires. (d) (1)A public agency other than a law enforcement agency may use an unmanned aircraft system, or contract for the use of an unmanned aircraft system, to achieve the core mission of the agency provided that the purpose is unrelated to the gathering of criminal intelligence.

In addition, public agencies other than law enforcement have to give the public reasonable notice that they plan to deploy a surveillance drone and describe its capabilities. Images and other information collected for public agencies by drones may not be disseminated outside of relevant public agencies and must be destroyed within a year if they are not obtained pursuant to a warrant or if they are not evidence in any claim filed or any pending litigation.

In addition, the legislation outlaws armed hunter drones:

Unless authorized by federal law, the bill would prohibit a person or entity, including a public agency subject to these provisions, or a person or entity under contract to a public agency, for the purpose of that contract, from equipping or arming an unmanned aircraft system with a weapon or other device that may be carried by or launched from an unmanned aircraft system and that is intended to cause bodily injury or death, or damage to, or the destruction of, real or personal property.

The bill awaits a vote in California's Senate. All states and the federal government should require that law enforcement agencies obtain a warrant based on probable cause before being permitted to fly surveillance drones.

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