Public defenders are paid by the state but they work for you.  It really depends, though, on what you "disagree" on.  If you are ignoring legal advice and refuse to listen to your lawyer say on your testimony as to the facts, the attorney can not suborn perjury. If, however, you wish to defend your self and your lawyer wishes you to take a plea, that is a different story. The lawyer has to defend you and take your best interests in to account.  You can request a new attorney if you feel that they are not fulfilling their obligation to defend you.