Is a Citizen's Arrest in California for DUI Legal?

In California, a police officer is not the only individual that can effectuate an arrest for a DUI.  A citizen’s arrest for DUI is proper when based on the citizen’s observation that the defendant was driving under the influence; in so doing, the citizen may delegate to a peace officer the act of taking the defendant into physical custody. This authority is vested in CA Penal Code 837.   For example, in one recent case, the Court ruled a citizen may make arrest for misdemeanor committed in his or her presence Johanson v Department of Motor Vehicles (1995) 36 CA4th 1209,  Also in another appellate court case, the Justices opined, a parking lot attendant who, observed defendant trying to exit parking facility by driving wrong way and into facility’s entrance gate, called 911 and a police officer and reported his observations to officer who made arrest,  and in another published California DUI case, the Court found, an inspector of Department of Food and Agriculture who stopped defendant’s vehicle at inspection station, observed defendant was intoxicated and reported observations to highway patrol officer who arrested defendant.  The bottom line is that a suspected drunk driver cannot escape liability because the person making the contact was not law enforcement.