Can a retired attorney without malpractice insurance notarize documents

Malpractice insurance has nothing to do with the issue; it would probably only cover malpractice in the practice of law, not notarial malpractice. A notary public does not have to be an attorney, although NJ attorneys are automatically empowered to perform the notarial function in NJ.  Thus, while a retired attorneys is no longer empowered to notarize signatures by virtue of his status as an attorney, he or she may have qualified and be a notary despite no longer being a member of the bar.  See N.J.S.A. 42:2-1.