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Supreme Court Rules Against Warrantless Blood Tests in DUI Cases

(Last Updated On: October 24, 2018)

Warrantless Blood Tests and the Supreme Court

In Missouri, police officers had broad discretion in administering blood tests to suspected intoxicated drivers without a judge’s approval.

The rationale for this discretion was that alcohol naturally dissipates over time, so a driver’s blood alcohol content would lower by the time the warrant was issued.

In 2013, the United States Supreme Court ruled in favor of a Missouri driver who challenged the police’s authority to administer a blood test without permission or a warrant.


Balancing Privacy Interests

The central issue in the Missouri case was whether or not the police’s interest in obtaining accurate evidence should outweigh a driver’s privacy interests.

Civil rights advocates argued that blood testing is an invasive medical procedure, which violates protection against unreasonable searches and seizures.

The argument against warrantless blood tests was that it would be unconstitutional to violate a driver’s privacy to his or her own body outside of extraordinary circumstances.


Providing a Bright Line Rule

Though the 2013 Supreme Court ruling affected the outcome in this case, it didn’t provide a bright line rule regarding warrantless blood tests.

Instead, the ruling dictates that police must use a totality of the circumstances test when determining whether or not a warrantless blood test is reasonable.

The Court did not provide specific guidelines as to how much time should elapse before police officers could reasonable order a blood test without a warrant.


Guiding Future Police Protocol

Even though the decision doesn’t exactly state when police officers can forego a warrant in administering a blood test, police will likely adopt more extensive guidelines on testing policies.

In particular, law enforcement officials will needs to narrow the emergency exceptions to the warrant requirement.

Police departments may also respond by speeding up the warrant process, testing suspected drunk drivers sooner.

The criminal defense attorneys of Thrush Law Group concentrate on defending those accused of DUI in Arizona.

Posted in Arizona DUI Law.


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