Statistical confidentiality is defined in Act no. 51-711 of 7 June 1951 (amended) on legal obligation, coordination and confidentiality in the field of statistics . It prohibits communication of any data relating to private and family life, and more generally, to any act or behaviour of a private nature collected during a statistical survey. This prohibition lasts for a period of seventy-five years unless special dispensation is given, after an opinion from the Statistical confidentiality committee, and the purpose is for official statistics or for scientific or historic research.
Economic or financial information may not be communicated to anyone for twenty-five years, unless special dispensation is given, after an opinion from the statistical confidentiality committee, and the purpose must not be to use this information for tax inspection or punitive measures.
Like all civil servants and government employees, statisticians in official statistical systems are subject to legislation and regulations on professional confidentiality and the obligation of discretion, which apply to the cases and information to which they have access in the course of their work.
Rules relating to statistical information
For private individuals, it is prohibited to publish data which would enable the indirect identification of respondents and their replies, a concept known as "impossibility of identification". These rules limit the level of detail allowed in information for dissemination. Very strict rules are set specifically for censuses. In the case of household surveys, identification via results is usually impossible, and no specific rules need to be drawn up.
For businesses, no results are published that concern fewer than three enterprises, nor any data where a single enterprise represents 85% or more of the total value obtained. However, the dissemination of lists extracted from the register of enterprises and establishments may mention economic activity, number of employees category and turnover size bracket.