You should definitely be talking to a local criminal defense attorney as soon as possible. Probation violations generally do not require the same level of proof that is necessary to secure a criminal conviction, and second offense DUIs generally carry heavier penalties than first offenses, so you have two separate issues to contend with, either of which could have serious consequences.
It's not clear whether you mean that your boyfriend wasn't given a breathalyzer test or wasn't given field sobriety tests. If there was no testing whatsoever conducted, that would certainly be to his advantage, but it doesn't mean that he's in the clear--only that it's one flaw in the process that might be useful in the hands of an experienced criminal defense lawyer.
I echo Mr. Chern's comments. Be aware that violating felony probation can land the defendant in prison, not just jail, particularly if he was recently granted probation (DA will argue defendant didn't learn lesson or not scared to go to prison) and/or has other indications that he is a poor probation candidate.
He should consult with anattorney immediately.
The failure to do FSTs, at least in Wisconsin, does not automatically result in the case being thrown out. I think the fact that no sobriety tests were done will certainly help your boyfriend though. It's impossible for anyone to say how much time he will do in jail without knowing more facts.
I agree with the following posts. Your boyfriend is on felony probation already, he picked up another DUI/DWI while he is already on probation. In California, any new law violation will automatically put his or her prior probation in a revocation status. He may also have had terms placed on his probation, such as no alcohol, which is common here in California. The fact that the police didn't do any sobriety tests, does not automatically "throw out" the charge. He needs to consult with his attorney right away.
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