Legal instrument is a legal term of art that is use for any written legal document such as a certificate, a deed, a will, an Act of Parliament or a law passed by a competent legislative body in municipal (domestic) or international law. Many legal instruments were written under seal by affixing a wax or paper seal to the document in evidence of its legal execution and authenticity (this could often remove the need for consideration in contract law); however, today most jurisdictions have done away with the requirement of documents being under seal in order to give them legal effect.