Appeal from a judgment of the Supreme Court at Special Term (Walsh, Jr., J.), entered April 5, 1982 in Clinton County, which denied petitioner's application for a writ of habeas corpus, without a hearing. Since a writ of habeas corpus is not an appropriate vehicle to challenge errors which were or could have been raised on direct appeal from a criminal conviction ( People ex rel. Douglas v. Vincent, 50 N.Y.2d 901, affg 67 A.D.2d 587; see People ex rel. Keitt v. McMann, 18 N.Y.2d 257), Special Term denied petitioner's application for a writ of habeas corpus based upon an allegation in the petition which stated that an appeal from the judgment of conviction had been taken to the Appellate Division, First Department, and was still pending review. It appears that the First Department had affirmed petitioner's conviction over a year before the application for the writ was made to Special Term, and petitioner ascribes the error to his "laymanship and lack of training in the law". By appending a copy of the First Department's affirmance to his brief on this appeal, petitioner urges this court to take judicial notice of his pleading error and, in effect, consider his application for the writ de novo. We decline to do so. Special Term's action in denying the application was entirely proper based upon the record before it. It would be a dangerous precedent, except in extremely unusual cases, for this court to abandon its appellate role in proceedings of this nature and exercise original jurisdiction by allowing defects to be remedied for the first time on appeal ( People ex rel. Gantz v. Herold, 24 A.D.2d 776, mot for lv to app den 17 N.Y.2d 420). Judgment affirmed, without costs. Mahoney, P.J., Sweeney, Main, Casey and Weiss, JJ., concur.