Every case is different based on the crowding situation available at the time. The minimum on a third is 120 days, HOWEVER, most people will receive what is called "Penal Code 4019" credits anyway. Currently, they are at about 50% "good time" credits. So he can assume 60 days at least. Whether its any lease is too hard to determine because there is not formula. It just depends on circumstances at the time of surrender.
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There is no hard and fast rule as to exactly how much time he will get. There is jail overcrowding but again how long he will actually spend in custody (if he gets any) for a DUI is not known without knowing other factors. For instance, you say this is his third DUI but when were the others? Is he currently on probation. Was this DUI or the previous ones violations where the BAC was over .15. Finally, as my colleagues pointed out, he faces even more scrutiny and potential custody time because he failed to. Again the question is how long ago did he fail to appear (one month, one year, etc)? All of this matter. Your best bet is to hire a local criminal attorney that can effectively explain his situation to the judge and argue for as little time as possible. There may be several other issues involved that may lessen the time he spends in custody. Good luck.
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