-An official instrument is one drawn up by a public official or a person charged with a public service, within the limits of his competence and in accordance with the legal forms (the Law of Evidence).

Official instruments are those in which a public official or a person charged with a public service records what was done at his hands or what he received from the parties concerned, in accordance with the legal forms and within the limits of his authority and competence.

If these instruments do not acquire official status, they have only the value of customary (private) instruments, provided that the parties concerned have signed them with their signatures, seals or fingerprints.

-A customary (private) document is any instrument issued by individuals without the intervention of a competent public official in drawing it up, and it derives its evidential force from the signature of the person who issued it. Examples include: the preliminary sale contract, the unregistered lease, the cheque and the bill of exchange, the trust receipt, quittances and promissory notes.

And under the Law of Evidence: a customary instrument is deemed to have been issued by whoever signed it unless he expressly denies the handwriting, signature, seal or fingerprint attributed to him. The heir or successor is not required to deny it; it is enough for him to swear an oath that he does not know that the handwriting, signature, seal or fingerprint belongs to the person from whom he received the right. Whoever has a customary instrument invoked against him and discusses its substance may not then deny the handwriting, signature, seal or fingerprint; if its author denies it, the party relying on the document is required to prove its authenticity.

The Penal Code refers to customary documents by the term “instruments of private persons”, meaning every instrument that is not an official document and does not fall within the scope of Article 214 bis.

An instrument may begin as customary and then become official, such as a customary contract that is deposited or certified, in which case its character at the time the forgery was committed is what counts.

The most important differences between the official and the customary instrument

The official instrument: drawn up by a competent public official – evidence of what is recorded in it until it is challenged for forgery.

The customary instrument: drawn up by a private person – evidence by the signature of its author unless he denies it.