It will definitely make a huge difference if he hires an experienced DUI defense attorney in his state to handle this sticky situation for him. Use this website to find a few excellent candidates who devote most or all of their practice to DUI defense, then take the time to call a few (or have him call a few) to find the best fit. He should move quickly on this.
Hire an attorney and there are several here on avvo from your area. I live in Moses Lake WA and am quite a ways away so I assume you would hire someone from your area.
Many DUI attorneys (including me) will offer a free initial consultation. The best place to start is by calling some attorneys in your area and setting up some meetings.
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