Yes, it is legal. Even if you were not on probation. but since you were on probation, you don't even have to be arrested in order for them to request. Most probation terms simply require that an officer suspect you are under the influence and driving.
As a result of your refusal, you will be facing "Refusal" charges with the DMV, which means (if you lose), your looking at at least 2 years without a license if this is your second offense, because of the refusal allegation.
Speak to a local DUI attorney about the case and discuss the details. See what they can do.
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Generally speaking, yes, and it is very common for them to do so in ultra-strict Ventura County. In fact, the arresting agencies in Ventura County have what is called a forced blood draw policy that dictates how this is to be done in just such a scenario. You need an experienced Ventura DUI attorney. Feel free to give me a call if you have any questions. Good luck.
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