While I am unsure what exactly will happen to you in Los Angeles, many jurisdictions will prosecute you for regular DUI instead of the provisions of the vehicle code for persons under 21. Therefore you will be facing a fine and a DUI school and depending on the how the jurisdiction reads the DUI punishment statute a minimum of 48 hours in custody. A public defender may be able to help you, however, a private attorney skilled in DUI defense may be able to provide expert advice as to the defenses and likely outcomes in your case AND represent you at the DMV.
Within 10 days of your arrest you need to contact the DMV and request a hearing regarding this arrest. By requesting this hearing you can assure a review of your case prior to any action being taken against your driving privilege. Unfortunately, because you are under 21 you are looking at a year long suspension if you lose either your DMV hearing or in court.
That being said, you have the ability to apply for a "critical need" license from the DMV depending upon demonstrated need. Again a private lawyer can help you with this process at the DMV as well, a public defender does not handle any aspect of your case except the court aspect of your case.
Finally, as the law currently exists, any alcohol related conviction in court or taken by the DMV will remain on your driving record for 10 years and on your criminal record for life or until you have it expunged. However, you should discuss the limitations of an expungement with a lawyer.
It sounds like you would be eligible for the public defender. Most likely, on your first court date the court will refer you to the public defenders office. Obviously, the public defenders office is very busy - but it is better than no representation at all or representing yourself. I encourage you to go to www.california-dui-lawyers.org to find an attorney in your area and get a free consult.
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