• 13
  • September
    2010

The Arizona Supreme Court recently rendered a decision on the appeal of Carillo v. Houser, a case interpreting Arizona's implied consent law for DUI suspects. The case was brought to the Supreme Court after the Court of Appeals ruled in September 2009 that a failure to object to a blood test does not constitute consent to having blood drawn under Arizona's implied consent law.

The Arizona Appeals Court overturned a lower court decision finding that a DUI suspect's failure to object constituted consent to having his blood drawn. The Appeals Court had remanded the case for a finding by the trial court on whether the DUI suspect's action in holding out his arm when informed police would draw his blood constituted an affirmative and unequivocal manifestation of consent. 

In recent years, blood draws have become a tool of choice for police in part because they provide superior evidence to breathalyzer tests, whose results have often been successfully challenged in court, leading to acquittals. Blood tests also provide evidence of drug intoxication, an increasing trend in DUI cases.

But implied consent laws such as Arizona's must tread a careful line so as not to run afoul of constitutional protections. The Arizona Appeals Court found that the implied consent law at issue, A.R.S. §28-1321, did not raise constitutional concerns, as it requires free and voluntary consent or a warrant.

Drivers suspected of DUI who fail to give consent for blood testing under A.R.S. §28-1321 are subject to automatic license suspensions. Police may not draw their blood unless they first obtain a search warrant. 

The Appeals Court noted that the law explicitly defines a failure to expressly agree to a blood draw as refusal. Observing the difficulties surrounding informed consent in the field, the court mentioned both language barriers to suspect-police communication and the effects of intoxication itself. The statute eliminated potential interpretation issues arising from these conditions by characterizing the absence of express agreement as a refusal. 

The Arizona Supreme Court agreed with the Appeals Court by ruling that Carillo's failure to object, or silence, when police stated their intention to conduct a blood test did not constitute consent.