Breath Tests at the Roadside

If you are stopped in California or any other state on suspicion of DUI you may be asked to take a breath test at the roadside. (Note that officers must have reasonable suspicion, or probable cause to make a DUI stop.)

A breath test conducted at the roadside before an arrest for DUI and/or DWI is a Preliminary Alcohol Screening (PAS) test. The purpose of the PAS test is to help officers decide if there is probable cause to arrest you for DUI and/or DWI.

To take the test you will be asked to blow into a portable breath analyzer (or “breathalyzer”) which will measure your blood alcohol content (BAC). In California and all other states it is a crime to drive with a blood alcohol concentration of 0.08 percent or higher.

If the roadside breath test (PAS test) shows you to have a BAC at or above 0.08 you will certainly be arrested.

Can you refuse a roadside breath test?

Unless you are under 21 or on parole, you have the right to refuse a roadside breath test (PAS test) in California and all other US states. It is 100% voluntary.

There are no penalties for refusing a roadside breath test.

Should you refuse a roadside breath test (PAS test)? Yes, absolutely.

It is in your interests to exercise your right to refuse a roadside breath test:

• The roadside is not an ideal environment for conducting a breathalyzer or any other kind of test.
• Officers may (and often do) lack experience operating breath analyzers
• Breath analyzers themselves are unreliable and are calibrated to calculate blood alcohol content for an “average” person.

What will happen if you refuse the breathalyzer test?

If you do not take the roadside breath test (and also refuse a field sobriety test) the officer will not be able to cite a failed breath test as probable cause for an arrest for DUI and/or DWI.

Instead, they must decide if their “observations” amount to sufficient probable cause for an arrest. For instance, the way you have behaved during the DUI stop, the smell of alcohol on your breath, and the way you have answered the officer’s questions. (This is why it is important to watch your behavior during a DUI traffic stop.)

If confident that they do, they will arrest you. However, you will be in a stronger position to fight a conviction for DUI and/or DWI than if you had been arrested for failing the breath test. (Remember, an arrest is not a conviction). Here’s why:

Once arrested (and not before) you will be required by law (in all states) to take a blood alcohol (BAC) test at the police station, regardless of whether you have already taken a test at the roadside. However, a good DUI lawyer can challenge the officer’s observations - whether they did in fact amount to probable cause for the arrest. If successful in this challenge (and there is a good chance they will be), the results of the BAC test will be inadmissible and your case dismissed.

Your DUI lawyer will not have the opportunity to defend you in this way if you have provided clear probable cause by taking and failing the test.

How to refuse:

Be very clear about your right to refuse a roadside breath test (PAS test). Police officers rarely advise drivers of their right to do so. In the anxiety of the moment you may find it difficult to remember your rights and be railroaded in to taking the test.

If the officer has not advised you of your right to refuse, ask if you have the right to refuse. You already know the answer – yes, you do – but getting the officer to say so allows you to politely respond that you choose not to take the test.

This is a less confrontational way to refuse the breath test than immediately saying, “I know my rights and refuse!” You do not want to behave in a way that allows officers to later describe you as uncooperative and hostile.

• Disregard attempts by the police officer to make you feel that you are not acting wisely by refusing the test.
• Do not be drawn into explaining why you do not want to take the test. Tell the officer that you simply choose not to take the test.
• Do not volunteer or agree to take the field sobriety test instead.

For an overview of all your DUI test rights, see Submit to a DUI Test or Refuse?

Copyright 2008 Caroline Mackenzie