According to Iran civil procedure law, data message and electronic documents has no evidential validity and could not be accepted in courts as evidence because of some problems that arise from legal evidence regime.

Because of low cost of producing and archiving of data message and its fastness in transferring, the usage of this technology is inevitable and is growing very fast .Therefore without evidential validity for data message and electronic documents , lots of legal problems would arise.

In international law and law of many developed countries different methods have been used to give adequate evidential validity to data message. One of these methods is , expanding the meaning of written and recognizing the equal functions for data message like written functions and therefore the electronic documents could have the same evidential validity like traditional documents.

One technology which is used in this method is digital signature that performs the main element of evidential validity of electronic documents. Digital signature assures the certainty of identifying the source of data message and its inalterability and would give the validity to electronic documents like official documents.

In international laws and the law of some developed countries, electronic signature has been recognized and has the equal validity like traditional signature .These laws declare that the electronic evidence should not refuse in courts just because of their electronic format.

In Islamic jurisprudent laws, any written documents or any other tools that lead the judge to the true fact and give him certainty could be accepted as evidence. A written document or data message which has the signature and is kept secure would have evidential validity and legal effect.