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Supreme Court: warrants generally required to draw a DWI suspect’s blood

Is a warrant required to compel a drunk driving suspect to take a blood alcohol test? A recent United States Supreme Court decision, Missouri v. McNeely, clarified this issue. Its decision will likely affect the rights of drunk driving suspects in Texas and across the nation.

Facts of case


The case began in Missouri when a man was stopped for speeding by a highway patrol officer. During the stop, the officer noticed that the man had bloodshot eyes, slurred speech and smelled of alcohol-telltale signs of intoxication. As a result, the officer ordered the man to submit to a field sobriety test. As the test was performed poorly, the officer also asked the man to submit to a breath test, but was refused.

Upon the man’s refusal, the officer transported the driver to a nearby medical clinic and had staff draw a blood sample to test for alcohol. The blood sample, which was taken about 25 minutes after the stop, showed that the man’s blood alcohol level was almost twice the legal limit.

At the trial, the man’s attorneys argued that the blood test results should be excluded from evidence, because the man’s constitutional rights were violated. The attorneys argued that since the officer did not get a warrant before taking a blood sample, it is a violation of the Fourth Amendment protection against unreasonable searches and seizures.

The prosecution countered this argument by maintaining that a warrant was not required due to “exigent circumstances,” or emergencies where the time it would take to get a warrant would likely lead to the destruction of evidence. Specifically, the prosecution argued that in the time that it would take to get a warrant, the man’s blood alcohol level would drop, due to the natural metabolism of alcohol. Therefore, there were exigent circumstances that excused the requirement of getting a warrant, the prosecution argued.

Ultimately, the Missouri Supreme Court agreed that a warrant was required before taking the blood sample. The case was then appealed to the U.S. Supreme Court.

Supreme Court’s ruling

In a 5-4 decision, the U.S. Supreme Court ruled that the dissipation of alcohol in a suspect’s bloodstream does not constitute an exigent circumstance, so a warrant is required to take a blood sample most of the time.

The court said that there may be situations were a warrant would not be required, if the ability to collect reliable evidence would be impeded during the time it would take to get a warrant. However, the court said, that such exceptions depend on the case’s circumstances and must be decided on a case-by-case basis. However, the court noted that modern technology, which allows police to reach a judge by email in seconds, would likely make such warrantless searches rarely permissible.

Consult an attorney


In Texas, the result of the ruling is already apparent. Many cities across the state have ordered their police departments to stop their practice of drawing a DWI suspect’s blood without a warrant, even though Texas law allows it in some cases. It is unclear at this point whether such laws will be declared unconstitutional because they conflict with the Supreme Court’s ruling.

Although the full impact of the court’s ruling has yet to be felt in Texas, drunk driving is still a serious crime that carries heavy fines and significant losses of freedoms. If you have been charged with DWI, an experienced criminal defense attorney can ensure that your rights are protected.