In April 2014, the Court of Justice of the European Union invalidated the Data Retention Directive, which unified the rules of the retention of selective data by Internet and telephone service providers and determined the accessibility of data by authorities in the member states. Despite this judgment, the Hungarian act allowing data retention is still in force. In October 2014, the Hungarian Civil Liberties Union started litigation against two major service providers in an attempt to get the Hungarian Constitutional Court to repeal the unlawful act.

The Hungarian Act on Electronic Communications instructs providers to retain telephone and Internet communications data for six months. This rule concerns "only" caller identity, caller location, the frequency of communications and other data of this kind, but excludes contents of communications. However, such data allows for drawing accurate conclusions regarding the private lives, everyday habits and travel patterns of concerned persons, even without knowing the contents of communications. Data retention of this kind therefore constitutes a serious intervention into the private sphere of concerned persons, as well as an infringement of the fundamental right to the protection of personal data.

At both European and national levels, attempts to justify data retention laws focus on their potential benefits in prosecuting serious crimes and fighting terrorism. Despite those arguments, the CJEU has already voided the European directive, and, at the national level, the Hungarian data retention act is not compatible with Hungarian constitutional requirements because it breaches the limits of the proportionality criteria. Due to recent reforms of Hungarian law and, specifically, to the jurisdiction of Constitutional Court, HCLU cannot directly refer to the court to establish that the law on data retention is against the Fundamental Law of Hungary (the country's constitution).

Amicus briefs wanted

Instead, HCLU requested in writing that the Internet or telephone service providers eliminate any retained traffic data; the service providers refused this request, citing the current legislation. HCLU then brought legal action against the service providers, and during the trial requested that the case be referred directly to the Constitutional Court (judicial initiative for norm control in a concrete case). A benefit of this move is that it can be made during proceedings in the court of first instance and forces the Constitutional Court to decide on the claim by a strict deadline (with urgency and not later than 90 days). On the first day of trial in the lower court, HCLU's arguments related to constitutional matters convinced the judge, who promptly referred the case to the Constitutional Court.

The Hungarian Civil Liberties Union is seeking urgent support from organizations active in the field to file amicus curiae briefs. In particular, it would be extremely helpful to have amicus briefs covering constitutional arguments about data retention that were taken into consideration in other countries. If you are willing to contribute to the case, please note the short deadline of the Constitutional Court and contact Fanny Hidvégi (, head of the Data Protection Program of HCLU, at your earliest convenience.