You can't fire a public defender because you didn't hire him. He was appointed by the Court and only the Court can remove him. If this indeed happened I wouldn't be so happy about it. Finding a decent private attorney can be difficult.
Mr. Loncar from Los Angeles has given the textbook answer. However, some judges are reluctant to give added time for a recently hired lawyer to get ready. This especially true if the new lawyer comes into the case right before the scheduled trial date. However, sometimes that works out just fine. I substituted in for appointed counsel about 10 days before a scheduled jury trial date on a second degree felony this month, and the judge gave me no trouble getting the trial moved off a few months to get ready. Your new lawyer should be able to orient you to what may go down in your particular case.
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