A public defender is a "real lawyer," and like any other attorney, he/she may be bad, good or great. You should check him/her out just as you would any other attorney. Google the attorney. Talk with the attorney and see whether he/she knows his business and seems interested in your case. Of course, if you can't afford private counsel then it doesn't much matter.... you get the public defender. Remember, the public defender is an attorney who is so committed to criminal justice that he/she chose to be a public defender for a time or forever in order to serve justice. Chances are you will get a very committed attorney, with a good support system of peers to whom he can turn to get advice. Give that attorney a chance. He will give you a chance, too.
Cannot tell if you are asking the question in general or as to a specific attorney [which a public defender (PD) is].
If your post is based on the fact that your PD is giving you some bad news, he or she is required to provide you with an honest assessment of your case. So is a privately retained attorney.
I have handled a number of governmental aid cases. They are excrutiatingly boring due to all of the paper [ tedious and time consuming but very simple]. But the paper is what contains all of the documents signed by the aid recipient/provider under penalty of perjury. The facts in contrast to those sworn statements may or may not be on paper but usually are.
I know about the requirement that the DA has to prove his/her case beyond a reasonable doubt . The reality is that some accountant/ bookkeeper for the state will take the stand and opine that you committed fraud. If you do not or cannot put on any evidence to contradict the state's witness, you lose.
The above is not intended as legal advice. The response does not constitute the creation of an attorney client relationship as this forum does not provide for a confidential communication.
I know some excellent attorneys in your area that are public defenders. Public defenders generally do not deserve the bad reputation they have gotten. The real difference is the amount of time an attorney will be able to spend on the case. Public defenders have an enormous case load and, quite honestly, I am amazed at how some of them function so extrordinately. Don't fall into the trap of hiring a cheap attorney to avoid a public defender. If the private attorney is too cheap they may not have any more time than the public defender and are likely not as good. Look on AVVO for a white collar crime attorney. Good luck.