Your question is a difficult to answer. Every case is different. The outcome of a case depends on a lot of variables (police report, etc.) your best bet to find a good defense lawyer that can answer all your questions, present your case in the best possible manner to the prosecutor and the court, and be someone you trust.
Did you refuse the portable breath test and/or the breath test at the police station? If you have any further question, we would be happy to assist you.
First of all, NO ONE EVER PASSES THE FIELD "SOBRIETY" TESTS. These tests are voluntary and there is no reason to perform them. They can only hurt you. Please don't offer any evidence to a police officer without talking to an attorney first.
Second, in Washington State pretext stops such as the one you describe are illegal. Until recently the burden of proof required to prove the stop was pretextual was insurmountable. However, recent caselaw is helpful and allows the court to use common sense instead of requiring an admission by the officer that the stop was motivated by your pulling out of the bar and not the taillight violation.
Get a good DUI lawyer. Your attorney will probably be able to do a lot of damage control. Whether you can keep this off your record entirely depends on way too many factors to discuss in a forum like this. DUI cases are complex. Hire a professional!
You need to speak to an experienced criminal defense attorney, who can review all of the evidence (police reports, video if any). Based on what you've said, there may be a basis to file a pretext motion, arguing that the officer illegal stopped you to investigate a DUI, and the tail light was just a pretext. If that motion were successful, the case would be ultimately be dismissed. However, the likelihood of that will depend on careful analysis of the evidence and what the officer says. There may be other issues with your case as well.
Speak to an attorney as soon as you can.
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