Does a warrantless blood test violate a defendant's Fourth Amendment rights?

People v. Brannon (1973) 32 Cal.App.3d 971, 108 Cal.Rptr. 620 and People v. Rawlings (1974) 42 Cal.App.3d 952, 117 Cal.Rptr. 651, held that, in the absence of constitutional violations, a blood alcohol test is not inadmissible merely because the test was administered in violation of Vehicle Code section 13353. The question, then, is whether the warrantless blood alcohol test administered here violated defendant's Fourth Amendment rights. We hold that it did not.