In State v. Axley, 132 Ariz. 383, 646 P.2d 268 (1982), the police stopped a vehicle matching the description of one involved in a robbery. Id. at 385-86, 646 P.2d at 270-71. After stopping the vehicle, the officers searched it and discovered weapons. Id. at 389, 646 P.2d at 274. The defendants claimed that the search of the vehicle was illegal because the police did not first obtain a warrant. Id. at 390, 646 P.2d at 275. The supreme court rejected that contention, holding that the automobile exception, as developed under Carroll, justified the warrantless search "due to the existence of probable cause plus exigent circumstances." Id. Exigent circumstances existed in Axley because "police officers would not have been able to detain the vehicle until a warrant issued," presenting a "now or never" situation in light of the car's mobility. Id. at 391, 646 P.2d at 276. In State v. Axley, the defendant asserted that the prosecutor's unwillingness to grant immunity to the co-defendant (who had pled guilty) resulted in the inability to secure the testimony of this essential defense witness. Id. at 387, 646 P.2d 268, 272. In that case, the court found that because the co-defendant's conviction could have been, and was eventually, appealed, the co-defendant still possessed the right to invoke the Fifth Amendment if called as a witness during defendant's trial. Id. at 388, 646 P.2d at 273.