If you failed a breath alcohol test, then Idaho will suspend your license anyway. Technically they do not suspend your California license because they do not have authority to suspend your California license. They essentially issue you a dummy license and suspend that license. Then they notify California that they suspended the Idaho license and California will follow suit just as they would had you gotten the DUI in California.
What you do next is call a defense attorney in the town you were arrested in, and do so quickly because you only have 7 days to appeal the license suspension with the Idaho Department of Transportation. If you miss the deadline you will lose standing the challenge the suspension.
You can also read the links I've attached for further help when it comes to DUI cases in Idaho.
I agree with Mr. Atkinson. I would just add that, in a DUI case, there is much more for you to worry about than just the license suspension (though the license suspension is a big and often devastating part of a DUI case). It is critical for you to meet with an attorney immediately and defend yourself against this charge. A qualified defense attorney will help you immensely.
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