DUI Implied Consent Law: Can I Refuse a DUI Breathalyzer or Blood Test?


Implied consent is a very controversial aspect of DUI law. Implied consent laws vary from state to state, but the basic concept is that by obtaining your driver’s license or simply by driving in that state, you have automatically given your consent to DUI tests such as the field sobriety test, breathalyzer, and blood or urine test. In some states you can be physically forced to take a DUI chemical test. In most states you can refuse, but will be punished for refusing.

Do DUI Implied Consent Laws Violate Your Constitutional Rights?

Many drivers believe or assume that they have the constitutional right to refuse a DUI breath test and other chemical tests, based on the right to privacy, protection from unreasonable search and seizure, and protection from self-incrimination. Depending on the circumstances in your case, you may be able to successfully raise one of these legal points in your defense, but states have found a loophole which gives them a lot of wiggle room.

Implied consent laws are based in the theory that driving is a privilege rather than a right. Another argument made in favor of implied consent laws is that if the test is not conducted within a short amount of time the evidence will be lost because alcohol is processed quickly by the body; this is said to justify a warrantless search.

The battle over the constitutionality of implied consent laws is ongoing, in part because the laws vary greatly from state to state. The unique circumstances in each case can make a difference, too.

When the U.S. Supreme Court ruled on DUI checkpoints, or roadblocks, it said that they in fact are a violation of the Fourth Amendment, but only a “slight” one and that the importance of combatting drunk driving outweighed the intrusion on civil liberty, and therefore deemed sobriety checkpoints constitutional. States that do not agree have made laws which ban the use of the roadblocks in those states.

We may see similar results regarding implied consent in the future.

DUI Implied Consent Penalties

The penalties for refusing a breath, blood, or urine test can include suspension of your driver’s license, steep fines, having an ignition interlock device installed in your vehicle before you can drive again, and even jail time. It varies from state-to-state, and in many states you can be severely punished just for refusing a chemical test, even if you are not convicted of DUI.

Some states have actually made it a crime in and of itself to refuse, and you can face criminal penalties for refusal. Other states have adopted civil or administrative penalties which can include automatic suspension of your driver’s license, fines, and more.

Typically, the officer must advise you of your implied consent rights and consequences of refusal when a breath, blood, or urine test is requested or the fact that you refused a chemical test cannot be held against you.

DUI Implied Consent and You

Each situation is unique, but in most cases it is not in your best interest to refuse a DUI breath test, whether you are sure that you will have a bad result or are innocent and refusing on principle. In many states you will be arrested simply for refusing the test. In some states, blood will be drawn forcibly and used as evidence against you, and you will face additional penalties for refusing the test.

You should always talk to an attorney who specializes in DUI defense in your state and any state you plan to drive in, if you want to find out how the laws will apply to you.