Can a judge appoint a lawyer to handle my mother's estate even though my brother and I were named as executors under her will?

The quick answer is yes! The designation of personal representatives, whether in a will for executors or for quardians of minor children, is an expression of the testator's wishes that carries great weight with the court. However, the court is not bound by a testator's wishes because, when the time comes to actually appoint someone to those positions, the testator's designation may not be capable of serving in that capacity or may not represent the best interests of the parties involved. Therefore, the court always has the discretion to appoint someone other than those designated under the will.

I would say, further, however, that the court cannot simply ignore the designations under a will. To do so would constitute an abuse of the court's discretion. So, in your case, I would suspect that there was some reason for the court to appoint a lawyer rather than you and your brother. That reason should be in writing by the court in it's decree appointing the lawyer.

If you believe the court acted incorrectly, then you have the right to ask the court to reconsider its decision. You also have the right to appeal the court's decision if you wish. The time for appeal is limited, however, so you should act quickly if you feel that an appeal is necessary.