Your question does not state what you are charged with, or your age.
It is rare to see a DUI charge filed, if that is what your are charged with, when the BAC is under .08, although it is legally possible. If you are charged with DUI based on alcohol alone, I would not seek a plea bargain for Neg 1st, because there is not much of a case for DUI. The prosecution may amend this one to Neg 1st on their own once they review it, as I don't see them wanting to go to trial on a .045. For Neg 1st, they would need to prove only negligent driving, and that you exhibited some signs of intoxication at the time. Unless they amend on their own, I would not offer to plead to anything.
If you are charged with driving while under age 21 with over a .02, then that is a different matter, with different penalties involved. Then, you are over that limit on the BAC, and a Neg 1st would probably be advisable.
Every jurisdiction in Washington with handle this case differently depending on the prosecutor and judge. If the only breath test you took was the portable, it is advisable to file a motion to suppress it if all of the WAC 448 protocols are not followed. In addition, portable breath tests ordinarily don't come into evidence at trial because they are a screening tool, not approved by the toxicologist. If you can resolve this case with a non-moving traffic ticket or even a Negligent Driving Second Degree (akin to a speeding ticket for insurance purposes) then you are in good shape. The actual elements are that you exhibited the signs of having consumed alcohol and also drove in a manner that was both negligent and likely to endanger person and/or property. In this case, the jury may find that you were not negligent given the circumstances.
You have two sets of problems: the criminal charge and the problems with the school. Neg 1 requires that a person drive negligently while exhibiting the effects of having consumed alcohol. If you have no prior criminal history a reduction is possible, but it depends on what the officer writes in his report.
There should be a process by which the decision to expel you from school can be appealed. But, there is usually a time limit on this. The officer is generally immune from prosecution for doing his job. Truth is defense to liable and slander and unless you can allege that he lied about the reading on the PBT, it looks like you are out of luck on that.
If you are over 21 years of age and the driving pattern articulated by officers is neglible, and you had never been charged in the past with any type of crime then there are negotiations to be made and depending on more details of the fact pattern some type of resolution can be reached. If you are 18 years of age and under 21, then a person can be charged with a DUI if they blew .02 or above.
In addition, you have the seperate headache of your school.
Regarding your school: Your school shoud have a procedure for their student conduct code and the grievance and appeals process, This procedure is governed by the procedures outlined in RCW 34.05, the Administrative Procedure Act.
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