Authentic act

A public instrument is any legal instrument (legal document) recorded with and authenticated by a public office or employee. To carry weight, any such instrument, must be genuine and authentic. Public instruments consequently must bear the name, title, and seal of the official that issued them, and should be written in the presence of witnesses who attested to them.

A public instrument is generally admissible in evidence without the necessity of preliminary proof of its authenticity and due execution. In other words, public instruments are self-authenticating documentary evidence. A presumption of regularity and validity attaches to public instruments; for the instrument to be rebutted, it must be proven in court to contain a willful material error.

Typical types of public instruments include:

Public instruments at civil law are generally known as public instruments (Germ: öffentlich Urkunde, Fr: acte public, Sp: instrumento público) and under Scots law as probative or self-proving instruments. These categories refer more to the level of evidenciary validity given an instrument in court. Under these legal systems, to be received as a public instrument, a document must be subjected to a number of conditions. These include:

Any such instrument is said to prove itself, that is, it has the privilege of being free from challenge or rebuttal at court.

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