Does a police officer have a duty to impound the vehicle of a driver who has been arrested for drunk driving?

More recently, in Green v. City of Livermore (1981) 117 Cal.App.3d 82, 172 Cal.Rptr. 461, police officers were held liable for the death and serious injuries of the occupants of a car struck by a vehicle driven by an intoxicated motorist after the car's previous driver had been arrested for drunk driving by the officers. There, the court held the officers had no mandatory duty to impound the vehicle or to arrest the passengers along with the previous driver. Nonetheless, it found they were negligent in failing to disable the vehicle after they had an opportunity to observe the passengers were also intoxicated and had ascertained one of the passengers did not have a valid driver's license. This holding implicitly imposes an obligation on the police once they have arrested an automobile driver for driving under the influence. That obligation is to investigate the physical condition and driver's license status of the passenger to whom the car is being released.

Furthermore, in Martinez v. Superior Court (1970) 7 Cal.App.3d 569, 576, 87 Cal.Rptr. 6, the court held police officers were not required to release the vehicle of a driver arrested for drunk driving to an individual claiming to be related to the driver, where the officers were unable to satisfactorily establish that person's identity.