Blood tests performed on drunk drivers did not violate constitutional protections under Fourth Amendment. In seven separate cases, each defendant was charged with misdemeanor driving under the influence (Veh. Code, § 23152, subds. (a), (b)) and filed a motion to suppress evidence pursuant to section 1538.5, contending that the blood drawn from his person subsequent to arrest and pursuant to the implied consent law should be suppressed under Schmerber v. California because the blood draw was not performed in a constitutionally reasonable manner. In each case, the arresting officer transported the defendant to the jail (or in one case a hospital) where phlebotomists or other technicians drew the blood. The officers observed the blood draw and testified that each defendant agreed to the test, no defendant experienced undue pain, and the draw was performed in a sanitary manner. The motions to suppress were denied in six of the seven cases. The appellate division of the superior court agreed with the defendants that the evidence should have been suppressed. The Court of Appeal transferred the cases from the appellate division and consolidated the cases for decision. Reversed. The means and procedures used to obtain a blood sample from an arrestee must be reasonable under the Fourth Amendment. If a physician does not draw an arrestee’s blood in a hospital, courts evaluate whether the conditions of the blood draw created an undue risk of harm to the arrestee. Testimony from a police officer who witnessed the blood draw may properly be considered in evaluating whether the blood draw was conducted in a constitutionally reasonable mannerexpert testimony is not required. Here, the officers’ unrebutted testimony showed that the blood draw did not expose the defendant to an unjustified element of personal risk of infection or pain and was not performed in a manner which created any undue harm or risk. The blood draws were conducted in a constitutionally reasonable manner.