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Telecommunications surveillance in Germany

Who can monitor telecommunications in Germany under what conditions? Can the intelligence services just do that, for no particular reason? Will the person concerned ever know whether his phone calls have been intercepted? The following article shall provide answers to these questions.

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In the Federal Republic of Germany, telecommunications surveillance is only possible on a legal basis. Corresponding legal bases can be found in numerous security laws such as the police laws of the federal and state governments, the Code of Criminal Procedure, and in the Act to restrict the Privacy of Correspondence, Posts and Telecommunications (G 10 Act).

In all cases, the monitoring measures are only permissible under the conditions laid down by law. Telecommunications surveillance measures conducted by intelligence services must be approved by a parliamentary commission. Measures taken by police and law enforcement authorities are subject to a judge’s authorisation. In addition, the measures are strictly limited in time and may only relate to ongoing communication.

Foreign authorities are prohibited from conducting telecommunications surveillance measures in Germany. However, in so far as telecommunication traffic happens via satellite or via foreign network components, which may be the case in particular concerning the Internet, it cannot be ruled out that communication is monitored by foreign authorities.

Intelligence services:

The measures in accordance with the G 10 Act as well as the personal data collected in connection with these measures are subject to the exclusive control by the G 10 Commission of the German Bundestag or, in the case of the state (“Land”) authorities for the protection of the Constitution, these measures are subject to the respective commissions of the respective state parliaments (“Landtage”). If you believe that you could be affected by any telecommunications surveillance by the federal intelligence services, e.g. by the Federal Office for the Protection of the Constitution (BfV), you can contact the

G 10-Kommission des Deutschen Bundestages
Deutscher Bundestag
Platz der Republik
11011 Berlin

However, under the G10 Act, such a restriction measure may only be conducted if there are real indications for the suspicion that the person concerned is planning, committing or has committed

  • crimes against peace or crimes of high treason,
  • offences threatening the democratic rule of law,
  • offences of treason against the country and posing a threat to external security;
  • offences against national defence,
  • offences in so far as they are directed against the free democratic basic order, the existence or security of the Federation or of a Land.

Details are set out in Section 3 of the G10 Act.
The same shall apply if there are actual indications justifying the suspicion that someone is a member of an association whose purposes or activities are aimed at committing offences directed against the free democratic basic order, against the existence or security of the Federation or of a Land.

In addition, under Section 5 of the G 10 Act, the Federal Intelligence Service may search international telecommunications relations by means of so-called strategic telecommunications monitoring on the basis of terms to be defined in individual cases. However, this is only permissible if the search terms are designed to assist in gaining insights into such dangerous situations for which the G10 Act allows this investigation procedure at all. This is admissible, for example, to counter the dangers of international proliferation of weapons of war, internationally organised money laundering and international terrorism.

The averting of dangers by the Customs Criminological Office

According to the Customs Investigations Service Act (ZfdG), the customs criminal authority may monitor letters, mail and telecommunications in order to prevent certain violations of the provisions of the War Weapons Control Act (e.g. trade in nuclear weapons, or production of chemical or biological weapons). Such monitoring measures must be ordered in advance by a court at the request to be duly motivated by the head of the administration and with the consent of the Federal Ministry of Finance. The implementation is subject to data protection control by the Federal Commissioner for Data Protection and Freedom of Information (BfDI).


Even possible telecommunication monitoring in accordance with the statutory provisions of Section 100a of the German Code of Criminal Procedure (StPO) can only take place in addition to further requirements if certain facts justify the suspicion that someone as a perpetrator or participant has committed one of the serious crimes listed in Section 100a para. 2 of the StPO, in cases in which the attempt is punishable, or in which the perpetrator has attempted to commit a criminal offence or in which the crime has been prepared by a criminal offence.

In fact, the vast majority of telecommunications surveillance cases are carried out by state police authorities, which are subject to the exclusive data protection control of the respective competent data protection supervisory authorities of the federal states. Data processing in the case of monitoring measures by federal authorities is controlled by the BfDI.

Who approves surveillance?

Telecommunications surveillance under the G10 Act must be requested by the competent ministry and approved by the G 10 Commission. All other supervision measures mentioned above are in principle subject to a judge’s authorisation, i.e. they must regularly be approved by a court in each individual case. In the case of imminent danger, the order may also be made by the Public Prosecutor’s Office or by a Federal Ministry, which, however, must be confirmed by the court within three working days.

Notification to those affected

Regardless of the law under which the telecommunications surveillance was carried out, the person concerned must be notified of this monitoring in principle after the end of the measure. The person concerned is thus given the opportunity to have the legality of the supervision verified by the courts. However, this notification may be postponed as long as, for example, providing information to the person concerned jeopardises the purpose of the measure.

Under strict legal conditions, notification can also be permanently excluded (cf. Section 12 para. 1 sentence 4 of the G 10 Act).