I am not sure why you have been on probation so long. It is usually 3 years from your date of plea or the date you were found guilty be a jury. Maybe you extended it to pay fines or finish classes, I don't know. But it seems like you may have a chance to have the court take you off probation in that it has been 4 1/2 years since the date of violation. Assuming there is nothing else that affects your case, you should probably consider hiring a lawyer who can bring a motion to terminate your probation in court. That is the way to go about it. Any of us on AVVO criminal law section can assist you with this. I'd suggest you call a few and get a free consultation.
I can only assume you're on 5 years probation because this was a second or third DUI.
Yes, you can make a formal request to terminate probation under Penal Code 1203.3, but you have to show "good cause" why they should end your probation. Documenting how many times you've been turned down for a job because you're on probation, etc. may help, but it's no guarantee. The biggest issue is that for a repeat DUI, they want to make sure you aren't at risk to drink and drive again. I don't know if you had the ignition interlock installed or if you have been through rehab, etc. All those things will help, but ultimately it's up to the judge whether or not to grant your request. They are very reluctant to end probation early on DUI cases. Why? Because there are certain extra conditions on you - such as not having any alcohol in your system when you drive - that go away if you're off probation. Because it's a repeat offense, they are probably reluctant to let you off probation without substantial information to support your request.
If you're serious about trying to do this, I'd strongly suggest you get a lawyer to help. If you try this on your own, I can just about guarantee they'll deny your request. Of course, there are no guarantees that with an attorney you will get off probation, but you stand a greater chance by working with a lawyer and putting together a good motion and packet of materials in support of your request.
The above answer is for general information only and is based on the information you posted. Every case is fact dependent, so to get a thorough analysis of your situation, you will need to consult face to face with an attorney licensed to practice in the jurisdiction where the incident took place. Do not conclusively rely on any information posted online when deciding what to do about your case.
I think it is safe to assume that your period of probation was set at 5 years.
However, the court will sometime entertain a petition for the early termination of probation, under Penal Code 1203.3, if you are able to demonstrate "good cause" why they should. It is definitely worth a try.
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