What's the noun for notarial? Here's the word you're looking for.
notary
(law, especially civil law) A lawyer of noncontentiousprivatecivil law who drafts, takes, and records legal instruments for private parties, and provides legal advice, but does not appear in court on clients' behalf.
(common law) A notary public, a legal practitioner who prepares, attests to, and certifies documents, witnesses affidavits, and administers oaths.
(law, Canada, US) A lay notary public, who serves as an impartial witness to the signing of important documents, but who is not authorised to practise law.