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Can You Be Forced to Take a Warrantless DWI Blood Test?


A DWI lawyer can represent you if you have been accused of driving under the influence of drugs or alcohol. When you are accused of driving while you are impaired, the prosecutor in the case has the burden of proving beyond a reasonable doubt that you actually were intoxicated and operating a vehicle.

In most situations, prosecutors will use evidence from tests performed to determine your blood alcohol concentration (BAC). A breathalyzer test or blood test that showed you have a BAC above .08 can be strong evidence of intoxication, although it is not conclusive and there are situations where people with a high BAC have been able to avoid being convicted even when a prosecutor has a toxicology test to present in court.

Because tests showing a high BAC do make it harder, in most cases, for you to be acquitted from a charge of impaired driving, defense lawyers will often help you to try to determine if you can have this evidence suppressed. Evidence that is suppressed isn’t allowed to be presented by the prosecutor as the prosecutor makes a case against you. Evidence can be suppressed if it’s collected in violation of your constitutional rights, so it’s important to know what police are and are not permitted to do. This means knowing whether or not you can be forced, under the law, to take a blood test even if the police don’t have a warrant.

The question of warrantless blood tests recently came before the U.S. Supreme Court and a decision was made that impacts the rights of drunk driving defendants. The Trevor J. Avery Law Firm can help you to understand what your rights are in relation to blood testing and can assist you in fighting to suppress any evidence that shouldn’t have been collected. Give us a call to find out more.

Is Evidence from a Warrantless Blood Test Admissible?

Police and lawmakers have long tried to find ways to make sure motorists are forced to submit to blood tests to confirm alcohol impairment, even without a warrant. In one case, Missouri v. McNeely, a driver was forced to take a blood test even though police did not obtain a warrant first. The defendant argued the test was a violation of his rights, while law enforcement justified the warrantless search by arguing there were exigent circumstances since the defendant’s body was quickly destroying the evidence by metabolizing the alcohol. The Supreme Court, however, found that the defendant’s Fourth Amendment rights had been violated.

Even though the McNeely decision should have put an end to the practice of forcing drivers to take blood tests with no warrant, this is isn’t what happened. Several states passed laws imposing penalties if drivers refused to take a blood test. This meant that while a driver could theoretically say no to a warrantless test, he’d be penalized for it. So, his “consent” to the test, if he gave it, was coerced by the threat of penalties.

These laws were challenged and a case called Birchfield v. North Dakota, which consolidated three lower court cases challenging the law, went before the Supreme Court. The Supreme Court decided that states couldn’t make it a crime to refuse to submit to a breath test when the police don’t have a warrant. Although states are permitted to impose penalties for not taking a breathalyzer test– since breathalyzers are less invasive than blood tests– they cannot coerce defendants into consenting to having their blood tested.

This means you cannot be forced to undergo a blood test to check for alcohol intoxication unless you agree to do so or unless police first obtain a warrant. If you’re subject to a warrantless blood test, you should talk with a DWI attorney so you can try to argue that the test was a violation of your constitutional rights and thus should not be admissible as evidence against you.

Getting Help from A DWI Attorney

You should talk with a DWI attorney as soon as possible if you have been arrested for driving under the influence of drugs or alcohol, as your attorney can carefully review the actions of law enforcement officers to determine if you can suppress evidence. If this is not the right strategy, the legal team at The Trevor J. Avery Law Firm can help you to find the best approach to take in responding to your charges in order to try to minimize penalties. To find out more about the way in which our firm can help you, give us a call at (910) 405-8459 or contact us online to speak with a member of our legal team.