Need a warrant for a DUI blood draw? According to SCOTUS it depends…

People generally prefer to know what is and is not allowed, often choosing to avoid the "maybes" in life. Unfortunately, the legal community does not always cater to this desire. The Supreme Court of the United States, or SCOTUS, recently issued an opinion that falls into the "maybe" category.

The opinion was supposed to determine whether or not a warrant was required before an officer could draw blood during a suspected driving under the influence (DUI) stop. Instead, the justices essentially stated that the answer depends on a wide range of circumstances. Ultimately, since so many circumstances can come into play, each situation should be considered on its own.

Details of the case

The case arose out of Missouri and involved a man who was pulled over for speeding and crossing the centerline. The officer requested a breath test to measure the presence of alcohol in the driver's system, and the driver refused. The officer arrested the driver on suspicion of driving under the influence of alcohol and took him to a nearby hospital to secure a blood sample for testing. At no time did the officer attempt to receive a warrant for this test.

The driver continued to refuse testing, but a blood sample was taken without his consent. The blood was tested and the driver was found to have blood alcohol content (BAC) over the legal limit. As a result, he was charged with driving while intoxicated.

The driver attempted to have the evidence of the blood test removed from court, arguing that the officer violated his Fourth Amendment right to protection against unreasonable searches by taking the blood without his consent and without a warrant. Ultimately, SCOTUS agreed with him.

The officer's only argument for taking the blood was his concern that the normal filtration of the blood through the liver would reduce the presence of alcohol. The officer was concerned if he waited for a warrant the blood would no longer provide an accurate reading since the liver would have filtered out a portion of the alcohol present in the driver's system. The Court found that, in this case, the officer's reason was not enough to justify taking blood without first receiving a warrant.

How this holding impacts Pennsylvania DUI stops

Holdings issued by the Supreme Court apply within Pennsylvania; as a result, this case will likely impact drunk driving stops in Pennsylvania.

According to the Supreme Court, a case by case analysis is required to determine if it was "impractical" for an officer to obtain a warrant before drawing blood for a BAC test. Arguing that an officer violated one's Fourth Amendment right by not getting a search warrant before taking a blood sample is just one of many defenses available against a DUI charge.