In Willett v. Superior Court (1969) 2 Cal. App. 3d 555, an officer saw the defendant driving with a nonfunctioning taillight and had probable cause to stop him and give him an equipment warning pursuant to Vehicle Code section 2806. (Id. at p. 559.) However, after examining the defendant's driver's license and registration, the officer did not promptly issue a warning and release him. Rather, he called for police assistance and further detained both the defendant and his two passengers while conducting a warrant check on all three. (Ibid.) He learned that defendant was a registered narcotics offender who had failed to keep his registered address current, and he was placed under arrest for that offense. As incident to the arrest, the officers searched the car and found illicit drugs; the defendant was charged with their possession. The Court of Appeal ordered suppression of the evidence because the "officers were not justified in detaining Willett beyond what was reasonably necessary to issue him a routine equipment warning. The search of the defendant's car was based upon his arrest on information learned well after his detention had exceeded constitutional limitations." (Ibid.)