Missouri Implied Consent Law for Chemical Testing in DWI/DUI/BAC Cases

Guilfoil Law Group April 20, 2021

Under Missouri's Implied Consent law, RSMo. 577.020, every driver who operates a motor vehicle in the State of Missouri by law has given implied consent to giving a blood, breath, saliva or urine sample to determine the alcohol content of their blood if arrested upon reasonable grounds to believe they were driving a motor vehicle while in an intoxicated or drugged condition.

The standard used is 0.08% BAC for adults over the age of 21; 0.02% for people Under 21. Under the law, you are presumed to know your rights concerning such testing, and give consent to such tests for the privilege of driving.

While the arresting officer under the statute has the right to ask you to perform two types of these tests as opposed to just a breath test, this rarely happens.

What is important is the driver does not get to choose the type of test. If he asks for a blood test, you cannot ask for a breath test because "you do not like needles."

Similarly, if he requests a breath test, you do not have the right to request a blood test in place of the breath test if you don't believe the results of a breath test are valid. However, there are rights you have that they do not have to tell you about but that they must give you if you are educated enough on the issues to ask for them.

For instance, you do not get to choose what type of test for which you are initially going to give your consent, i.e.-if they ask for a breath test you do not get to substitute that breath test with a blood test.

However, you do have the right if you consent and take the initial breath test to an independent test at your own expense. Of course, they do not have to tell you of this right, and I have not had a single client who has yet exercised this right, but it exists!!

The police probably do not have to transport you to a hospital for the independent test, but there is no question they have to allow you access to someone who can give you the test if you are knowledgeable enough to have someone who can help you when you need it.

You also have the right to 20 minutes to speak with an attorney in Missouri for advice on whether or not you should consent to a chemical test or refuse it.

They also do not have to advise you of this right…. Know your rights and exercise them!

Put the number of a known DWI attorney into your cellular phone so you may contact them when you need it. Our office may be reached by phone 24 hours a day for advice on whether you should consent to a chemical test. Be sure to also ask your attorney about making arrangements for your independent chemical test.

If you get an independent blood test, they can often be used to refute an unreliable breath test if taken soon thereafter.