You always have a right to represent yourself, whether it be on appeal, or in the lower courts. Keep in mind the court will expect you to follow the rules as an attorney would, so get the rules and read them closely.
Answers posted here are suggestions only, and are not intended to replace advice given by an attorney that you hire.
Can you represent yourself-yes, however, I wold advise you doing so is unwise. Appellate stage of the legal proceeding is a complex arena and having a experienced attorney by your side is paramount in increasing your chances of success.
Inna Rifman, Esq.
You can but it is better to have a lawyer.
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If I were representing you on appeal I would file my own brief, too, and would not rely on the work done by a previous attorney, let alone by a pro se litigant. Think this through before you trash a lawyer who may be doing the best thing for you. You do not have a federal constitutional right to represent yourself on appeal, but most states will let you do it as a matter of state law or rule of court. It is as poor an idea as I can possibly imagine, but at least have no one but yourself to blame if you fail.
Your other post said you haven't filed the brief yet. If that's accurate, you can fire your attorney and re-edit and rewrite the brief however you want. Is the current attorney retained or assigned? If assigned, he can withdraw only with court permission. If retained, you should contact the App. Div. Clerk to find out how you discharge him of record so you can proceed pro se. Courts are often reluctant to allow an attorney to withdraw if that will leave a client without counsel, unless the court is very sure that's what the client wants.
What makes you think time is running out? There are no filing deadlines for criminal appeals in the Second Department.
I am not your attorney and any posts/messages or responses to posts/messages can not and do not establish an attorney-client relationship. You should not rely upon free legal advice, and I disclaim any liability for the outcome if you do. Any opinions offered on matters outside New York State are for general informational purposes only.
You have the right to represent yourself. However, it is not a very good idea. A better route would be to file a supplemental brief along with your attorney's if you feel there are additional substantive points that should be made.