breathalyzer vs blood test fourth amendmentThe Fourth Amendment to the United States Constitution reads “The right of the people to be secure in their persons, houses, papers, and effects, against unreasonable searches and seizures, shall not be violated, and no Warrants shall issue, but upon probable cause, supported by Oath or affirmation."

In the ongoing battle between obtaining information and protecting the rights of the accused, one of the biggest points of contention has always been searches. What constitutes an unreasonable search? What requires a warrant, and what does not? When is probable cause enough to search, and when must a law enforcement officer try for a warrant from a judge.

Again and again, it seems the DUI stop is the front line of this struggle: Can police order you to take a test? Breathalyzer vs. blood test? How much testing is too much? In many places, laws criminalize refusing breath and blood tests for DUI offenses, and last month, based on three cases in the midwest, this very subject was brought up before the Supreme Court.

The Supreme Court Rules on the Issue: Breathalyzer vs. Blood Test

Breathalyzer vs blood testIn their ruling, the US Supreme Court stated that police must have a warrant to obtain blood samples for people accused of driving under the influence of alcohol. Though breath tests can still be done without a warrant, requiring the court’s involvement in getting blood results is an important step in protecting the rights of the accused. A blood test without a warrant, the court ruled, is in violation of the Fourth Amendment.

Justice Samuel Alito explained his reasoning behind the ruling.  “A blood test, unlike a breath test, places in the hands of law enforcement authorities a sample that can be preserved and from which it is possible to extract information beyond what can be learned from a breath test.” 

breathalyzer vs blood test copIn other words, in the debate of breathalyzer vs blood test, not only is the blood test more intrusive than the breath test, it gives much more information to the police. When you take a breath test, the test measures only one thing: the blood alcohol concentration (BAC) detected from your breath. With a blood test, there is so much more data available. A blood sample can be kept permanently, and subject to more tests at a later time.


Facing a DUI Charge in Arizona

breathalyzer vs blood test checkpointThis ruling does not affect the current practice by police in Arizona. Police already get warrants for taking your blood, if the driver refused. Usually the driver does not refuse. Part of the reason drivers do not refuse, even when they know the blood will probably have alcohol in it, is because in Arizona if you refuse to give a breath or blood sample after you are arrested for DUI, your licensed is revoked for a year. Even if you have absolutely no alcohol in your system. So police do not usually need a warrant because they just threaten you with the loss of your license for a year to get you to comply.
In April, the Arizona Supreme Court ruled that motorists can not be threatened with the suspension. However, the suspension rule is still the law. So police have to be careful about informing you of the rule without appearing to threaten you or tell you that you do not have the right to refuse. And if you do refuse, they have to get a warrant.   
If you're pulled over for a suspected DUI, first and foremost, be polite to the officer. Arguing and being belligerent will not help your case. If the officer asks you to do roadside tests, you have the right to refuse to do them and you should. If you are arrested and the police ask you for a breath or blood sample, you should comply. Do not require a warrant unless your license is already revoked or you have prior DUI convictions. Also, you should ask to speak to an attorney. It's vital to get an experienced lawyer who will be in your corner.

Contact Phoenix DUI Attorney Burges McCowan for a free consultation, and ensure that your rights are upheld while mounting the best possible defense.