Your son will be subject to the laws of the other state. If, for example, he drove over to Washington, and picked up a charge there, he will have to resolve his matter under Washington's system of laws.
The other problem you're going to run into is a suspension in Oregon. Most states are members of the Drivers license compact. That means that if, for instance, your son is convicted of a DUII in California, California will notify Oregon (because he has an Oregon License) and Oregon DMV will then suspend his license for one year. So first, find out if there is a diversion type program in the state where the incident occurred and make every effort to get in and complete it. Then, if there is a conviction, be aware of the coming license suspension.
NO. No chance at all. However, Washington has a number of very fine DUI lawyers. If you need names, you can call me. If your son gets a very good attorney, he will probably be able to have the case reduced to a negligent driving offense. It is very similar to DUI Diversion in Oregon, in effect.
I think the question may have been misunderstood...
As I understand it, you fear that your son will be convicted of DUI in some other state (let's just say California). If your son wants to participate in a California diversion program, that will likely mean taking certain classes, attending AA sessions, etc. But, if your son lives in Oregon, it would be extremely difficult for him to go do those things in another state.
However, if your son finds similar classes in Oregon, classes that seem to fulfill all the requirements of the other state's diversion program, a judge in that other state may allow your son to complete the diversion program, possibly even entirely from another state.
Naturally, you would need to seek out an attorney in the state where your son was arrested, in order to determine whether this is possible.
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