Knowing your rights is important to either completely avoiding a DUI charge or minimizing the evidence the State can use against you if the prosecutor does file charges.
1. In order to pull you over, the police must have either (1) probable cause that you've committed a traffic infraction or (2) reasonable suspicion that you're committing a crime.
The first step in avoiding a DUI is not getting pulled over. Once a police officer pulls you over, he'll start looking for evidence of intoxication (red bloodshot watery eyes, slurred speech, fumbling movements, etc.). Regardless of how much you've had to drink, these descriptors will almost always end up in the police report. Avoid this by not doing anything that can get you pulled over -- make sure your tabs aren't expired, make sure your car is complying with regulations for things like the position of the license plate, the amount of noise and pollution your exhaust pipe is producing, don't roll a stop sign, don't speed. You would be surprised how well cops know the infraction code when it comes to thinking up reasons to pull you over.
And, of course, the best way to avoid getting charged with DUI is to not drink and drive...but you know that!
2. Understand that the POLICE OFFICER IS NOT YOUR FRIEND
This may seem obvious, but it is amazing to see the effect that a seemingly friendly police officer can have on a person who knows he or she is in trouble. You've probably heard that it will improve your outcome if you are nice and polite to the office. That is true -- the police officer will treat you with more respect and the prosecutor will definitely penalize you if the police report says that you were rude or insulting to the officer. BUT, this does not mean that you should admit to anything incriminating to the officer. Give him/her your identifying information and registration (have this ready before the officer approaches so he can't say that you fumbled while getting it), but invoke your RIGHT to REMAIN SILENT when he keeps asking you questions about whether you have been drinking. Even if it seems socially awkward, and you feel like you can trust this particular officer, he is not your friend! Everything you tell him will end up in the police report and used against you in court!
Keep thinking about the words "Damage Control" -- if you're driving drunk, chances are you will be arrested. Minimize the evidence that will be used against you by giving the officer by keeping your mouth shut.
3. The Portable Breath Test (PBT) and Field Sobriety Tests (FSTs) are VOLUNTARY
A PBT is a portable test that measures your blood alcohol content during the stop. It is very unreliable. FSTs are the tests that you do on the side of the road. They are designed to show that you are impaired, and even if you are not drunk, you can "fail" these tests.
It is very common for officers to fail to tell a suspected drunk driver that the PBT and FSTs are voluntary. They are required to do this, but they almost never do it, and somehow they end up saying that they did in their police reports. Often, they will just hold the PBT up to your mouth and tell you to blow or order you to get out of the car and do the field tests. So, it's important to know that you can SAY NO TO THE PBT and FSTs.
4. In order to arrest you, the police officer must have probable cause that you have committed DUI or another crime
A police officer cannot arrest you unless he has gathered enough evidence to lead him to believe you have committed a crime. Later, the court will review this question, and if the officer did not have probable cause to arrest you, it will suppress all evidence gathered after the arrest. This can lead to dismissal of the DUI. And this is why it is so important to minimize the amount of evidence the officer can gather after he pulls you over. If you remain silent, do not perform the breath test or the field sobriety tests, the officer has very little evidence to work with, and the officer will have trouble justifying the arrest to the court.
5. Know that refusal to perform the breath test at the police station can result in automatic suspension of your driver's license
Even though it is best to refuse the PBT during the stop, it is usually the best idea to perform the breath test at the station because a refusal automatically results in suspension of your driver's license and the high penalties associated with blowing a blood alcohol level over .15 (the legal limit is .08). This issue has become more complex with recent legislation, however, so it is important to talk to a Washigton DUI attorney for advice on your particular case.
6. Request an attorney as soon as possible
If the police officer decides to arrest you, request to speak with a Washington criminal defense attorney. Not only can an attorney help guide you through the arrest and resulting criminal case, she can also observe your level of sobriety at the time of arrest. And if the police fail to comply with your request in a timely manner, your attorney may be able to suppress evidence gathered after your request!