There are two types of breathalyzer tests that may be requested in a DUI case. One is optional and will not cause any issues for you if you refuse. The other will result in at least a 270 day suspension of your license or the ignition interlock for one year if you elect not to take it.

A portable breath test ("PBT") is sometimes offered at the scene by a police officer if he is unsure whether you are impaired or under the influence. It is usually suggested after you perform field sobriety tests and before you are arrested. This test is optional and there are no consequences to refusing the PBT other than you will almost certainly be arrested if you refuse it. The PBT results are inadmissible if offered by the prosecution because these tests are not as reliable. The test results can be introduced by your attorney.

If you do well on the PBT, the officer may choose to let you go without an arrest. However, the officer will arrest you if your PBT results are at or above the legal limit or even if they are close to .08.

The regular breathalyzer test has far more severe consequences. These are generally performed at the police station by a certified breathalyzer technician. If you refuse this breathalyzer test, your license will be suspended for 270 days for a first refusal and two years for a second one. You have the option of electing the ignition interlock for one year in lieu of the suspension. A refusal also carries an enhanced penalty of an additional 60 days in jail. A refusal is also admissible at trial to establish that you were impaired or under the influence of alcohol.

The decision whether to take the regular breathalyzer test is a complicated one. If you did not drink or had little to drink, take the test. You should be below the legal limit. On the other hand, if you "tied one on" and know you will be .15 or above, taking the test may only create evidence for the prosecution. If you fall in the middle and think you may fall below .15, you may want to take the test because you may be eligible for a restricted license for work and school. Repeat offenders may face greater consequences if they blow a high result and CDL drivers face severe consequences for a refusal.

In summary, the PBT is optional and cannot come back to haunt you. The regular breathalyzer test can have severe consequences to your license.