Okay - so you've gotten advice from "everybody" who tells you to hire an attorney. I understand - not everyone in in a position to retain private counsel. If there is any way possible for you to consult and retain an attorney on your own, I would strongly suggest it.
As a whole, the public defenders are excellent criminal attorneys. That's what they do. They aren't part-time criminal attorneys who also dabble in real estate, divorce, personal injury and anything else that comes their way. Of course, every individual public defender (like every private criminal defense attorney) is different. There are some that are better than others in both private and public law.
The difference with a private attorney and the public defenders are two main ones: First, you can't choose your public defender. Your case is assigned to an attorney at random. It's up to you to hope yours is one of the better ones and that their personality and yours match, not to mention that they have the time necessary to devote to your case. If you go with a private attorney, you can choose the one you feel comfortable with after speaking to as many as necessary for you to make your choice. Second, it's a matter of volume. The public defenders have an enormous case load. They may not have time to meet with you aside from a couple of minutes in the hallway to tell you what the plea offer is. If you think you have particular twists that will require some in-depth discussions with an attorney, typically public defenders aren't equipped to handle that. Will they fulfill their ethical obligations to their clients? Absolutely. It just may take a bit of extra work and time to be able to get the time necessary to fully discuss your case with your assigned attorney.
Having said all that - the choice is yours. Yes, you should have an attorney when facing criminal charges, as they can greatly impact your initial freedom as well as your life long into the future.
Your specific questions:
1. Does it go in my record and affect my employment process? If convicted, yes it does.
2. Do I need to have a public defender if I don’t hire any attorney? Does it really helpful? See above about having an attorney and private vs. public attorney.
3. Should I plead that I am guilty in court or not? Pleading guilty convicts you. If you want to just walk in and have a conviction without exploring legal or factual defenses, sure - plead guilty without a fight. Not advised.
4. My court date is on May 18, 2009 and I am moving out to another state at the end of May. If I cited for public service or any type of classes can I attend them in another state? You may be able to. That's something that you'd need to work out with your attorney and the court.
5. What do you predict about my case in my court day? Unfortunately, my crystal ball is in the shop. Every case is unique. This is why you should either retain an attorney or be prepared to discuss this with your assigned public defender if you qualify.
Maybe the links below will help - some basic information about theft charges.
Everyone has a freedom against self-incrimination but an online site like this one is not private. What you post here may be used against you. No one can say what the evidence is against you so at least remain silent and do not incriminate yourself without speaking to a lawyer.
You need a lawyer so get one. ASAP!
Read my Legal Guide "What is the Right to Remain Silent?
You might find my Legal Guide helpful "How to Choose A Lawyer For You"
You might find my Legal Guide helpful " What Do I Tell My Lawyer"
No one can know what the record is in the case because online we cannot see your documents. You need a lawyer. Check with a lawyer in your locale to discuss more of the details.
Good luck to you.
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