If you have a blood alcohol level below the legal limit, as determined by a breath or blood test, the police and prosecutors often still file charges. [I’m guessing that you mean you had a BAC of 0.07%.] Usually, the prosecutor will file charges if there was a time period between the driving and the breath or blood test, that would allow them to make the argument that at the time of the driving the person was at or above the legal limit. Then, the person’s body metabolized some of the alcohol after the driving, but before the breath or blood test. Thus, the person was DUI at the time of the driving, even though he or she was below the limit at the time of the test. This is very common for police and prosecutors to do in DUI cases. And, it is a very important reason to get a highly skilled DUI attorney. These cases can frequently be beaten.
Because there are two ways to prove a DUI: you drove and your BAC was .08 or higher; or, if the BAC is under .08, you drove while affected or impaired by alcohol or any drug. This can be proven by the officer's testimony of impaired driving. If you were pulled over for something other than that (e.g., expired tabs), the charge might be easily challenged.
You need to consult with an Oregon DUI attorney who can evaluate your case. The prosecutor will not be likely to dismiss based on you asking for dismissal. They know you do not have the legal knowledge necessary to draft and file a motion and brief on the issue of an unlawful stop/arrest. You really do need a lawyer who focuses on DUI defense..
This answer is my personal opinion, offered for informational purposes only. It is not a legal opinion, nor is it legal advice, nor does it create an attorney-client relationship with anyone reading it.
Just thought I should add -- if you're Diversion-eligible, some prosecutors charge you and hope you'll plead guilty/no contest and enter DUII Diversion. As Bart mentions, there are many reasons to fight this case. "DUII" in Oregon means .08% BAC at the time of driving or ADVERSELY affected by alcohol at the time of driving. We're all "affected" by alcohol after the first sip -- we feel more relaxed, comfortable, social (there's a reason why every Bar and Bench and law school event has booze). That doesn't make use "adversely affected," or impaired, because of one drink. Some special interest groups would like to make it illegal to drive if you've had anything to drink, but so far our society and legislatures have disagreed. It's only illegal if you've had too much. Finally, I should add that alcohol absorption (and the question of your BAC at the time of driving) should be explained to you in your initial conference with your DUII lawyer.
Most states have two separate and distinct DWI/DUI crimes (they do not violate double jeopardy):
1. One is called Common Law DUI/DWI. This is strictly based upon your behavior and the opinion of the police (deputy, trooper, officer). All states have their own specific definition, which must be looked at by an attorney and compared to your situation. In NYS it is based upon one specific case, People v. Cruz, which states that the prosecution must prove that a person is mentally and physically incapable of operation of a vehicle as a reasonably prudent (careful/safe) driver.
2.The second DWI/DUI is called DWI "per se" because is based in a specific level of B.A.C. either by an indirect breath measurement or by a direct blood measurement. This is an opinion of a test result. The result may be challenged as being inaccurate. It is after all merely a number.
The police will charge you with DUI/DWI common law if they cannot charge you with DWI/DUI per se. If they can charge both they will. In NYS, they could also charge DWAI (driving while ability impaired) which is a presumption at .06 BAC.
DWI/DUI common-law can be charged with or without a BAC. In refusal cases this is the typical charge.
I am licensed in NY, NJ, PA, and FL but NOT OR
This is not a substitute for legal advice, nor is it to be construed as legal advice. I would recommend discussing this matter with a lawyer with an immigration attorney and a DUI lawyer from OR.