Yes.

If so, what are they? Are these only notarial acts or also acts of other authorities?

According to Article 1317 of the Civil Code, the authentic instrument is that which has been issued by public office-holders having the right to issue instruments in the place where the instrument was drawn up, and with the required formalities. Then, according to Article 1319 of the Civil Code, the authentic instrument is fully authentic as regards the agreement it contains between the contracting parties and their heirs and successors.

These are therefore notarial instruments, but also instruments of the courts or civil registrars.

Yes, according to Article 1319 of the Belgian Civil Code (hereinafter: C.C.) which states that “The authentic instrument is evidence of the agreement between the contracting parties and their heirs or successors in title”.

Yes, all instruments that fall within the definition of an authentic instrument as defined in Article 1317 C.C. have a reinforced probative value as stated in Article 1319 C.C.
“An authentic instrument is an instrument that has been drawn up by public officers having the right to draw up such instrument in the place where it was drawn up and with the required formalities”.

According to Belgian law, an authentic instrument is proof of its content, which are elements noted and verified by the competent authority. It is binding on the parties, on third parties and on judicial authorities. It is only possible to prove the contrary in a complex procedure similar to the procedure for challenging a judicial decision on the grounds of judicial bias: the procedure to challenge the authority of a document.

Authentic are: the date, the place where the instrument was drawn up, the fact that the parties have appeared before the notary, that they have made a number of declarations in his/her presence, that they have made certain payments, etc. However, any references the veracity of which the public officer was unable to ascertain in person and which have only been included in the instrument on the basis of the parties' declarations, are only evidenced by the authentic instrument until the contrary is proven according to the rules of ordinary law (Art. 1319-1320 C.C. and Art. 895 et seq. of the Judicial Code).

Before which authority: The Court

According to which procedure (state the applicable rules):
The reinforced probative value can only be challenged by way of the procedure to challenge the authenticity of a document. This procedure is governed, for civil matters, by Articles 895 et seq. of the Judicial Code and, for criminal matters, by Articles 448 et seq. of the Code of Criminal Procedure.

In civil matters, the procedure to challenge the authenticity of a document may be principal or incidental. In the latter case, the judge hearing the main case has jurisdiction to rule on the authenticity of a document. In both cases, the judge orders the parties to appear before him/her and orders the defendant in a civil case to produce the alleged false document. If the defendant appears and declares that he/she doesn't wish to use this piece of evidence, the judge takes note of that and has an official report drawn up. However, if the defendant declares that he/she wants to use it, the judge initials the document and orders it to be handed over to the court registry. After having taken all necessary investigatory measures, the judge will rule on the authenticity of the document. If the judge declares it to be false, the ruling is mentioned in the margin of the document in question and an official report is drawn up. The document is seized and sent to the public prosecutor, together with a copy of the ruling declaring it to be false.

In criminal matters, if in the course of proceedings an authentic instrument is produced which one the parties claims to be false, such party shall call on the other party to declare whether or not they intend to use such item. If the party declares that they don't want to use it or makes no declaration within eight days, the disputed item is rejected in the trial. However, if the party declares its intention to use it, the court hearing the main case is incidentally seized with the matter.

Within what timeframe:
In civil matters, the judge may immediately rule on the issue if he/she deems it can be ruled upon as it stands. Otherwise, the judge may decide on any necessary investigatory measures; the judge can either take such measures him or herself or direct that such measures be taken in accordance with the provisions on the verification of documents (Art. 902 of the Judicial Code).

In criminal matters, if the party who has argued that the document is false alleges that the party who has produced it is the author or an accomplice or, if it emerges in the proceedings that the author or the accomplice is alive and prosecution of the crime is not time-barred, the charge will be prosecuted in due form.

In a civil court case, judgment will be suspended until the ruling on the authenticity of the document is issued.

If crimes, offences or infringements are involved, the court or tribunal seized has to rule first, and after having heard the officer in charge at the public ministry, whether or not judgment should be suspended.