Berlin: Police can secretly enter homes for state trojan installation

To collect data from IT systems, investigators in Berlin can secretly search suspects' rooms. This is in a Police Act amendment.

(Image: Trismegist san/Shutterstock.com)

Dec 5, 2025 at 12:29 am CET 6 min. read By Stefan Krempl

With the majority of the coalition of CDU and SPD, as well as the votes of the opposition AfD, the Berlin House of Representatives passed a comprehensive amendment to the General Security and Public Order Act (ASOG) on Thursday. The reform grants the police powers that deeply interfere with fundamental rights and cross previous red lines of the capital's security policy. While Interior Senator Iris Spranger (SPD) defends the law as a necessary update for the digital age and the fight against terrorism, critics see it as a disproportionate attack on privacy.

A bone of contention is the combination of digital surveillance and physical intrusion: In order to monitor encrypted communication, investigators will in future, according to the Senate draft and the Änderungen der Abgeordneten, not only be allowed to hack IT systems but also to secretly enter suspects' apartments. The explosive innovation is hidden in paragraphs 26a and 26b. These regulate so-called source telecommunications surveillance (Quellen-TKÜ) and secret online searches. In order to intercept communication on devices such as smartphones or laptops before or after decryption, the police may use malware such as state Trojans.

But the new Police Act goes a step further: If remote installation of the spyware is technically not possible, paragraph 26 explicitly allows investigators to "secretly enter and search premises" in order to gain access to IT systems. In fact, Berlin is thus legalizing – as Mecklenburg-Western Pomerania did before – state intrusion into private apartments in order to physically install Trojans, for example via USB stick. IT security experts not only warn about leaving vulnerabilities open. They also see a constitutional violation in the combination of residential space violation and digital investigation.

This infringement on the inviolability of the home is accompanied by paragraph 24c, which newly regulates the use of bodycams. While their use was previously focused on public spaces, police forces are now allowed to activate the cameras in private homes and other non-public areas if there are concrete indications of a danger to life or limb. Although the legislator emphasizes the aspect of self-protection, opponents fear that this will lead to audiovisual surveillance in the most intimate retreat of citizens in practice.

Berlin is also technically upgrading in public spaces. With paragraph 26e, the cell tower query is being expanded. In the future, the police will be able to request traffic data from all mobile phones from network operators that were located in a defined cell tower area at a specific time. This enables the creation of movement profiles of thousands of innocent citizens through grid searches, who may have coincidentally been at a demonstration site.

In parallel, paragraph 24d creates the legal basis for the use of automatic license plate recognition systems. These scanners capture license plates in flowing traffic and compare them with wanted databases. Paragraph 24h also allows the use of technical means against unmanned systems such as drones, including taking over control.

Another aspect that is met with criticism in expert circles is the introduction of paragraph 28a. This allows the police to perform biometric comparisons of faces and voices with publicly accessible data from the internet. This enables the police to conduct automated searches on social networks or photo platforms, for example with automated facial recognition, using material from video surveillance to identify individuals.

In addition, the new paragraph 42d allows the further processing of personal data for "training and testing of artificial intelligence systems." Thus, the representatives of the people create a legal basis for using real police data – such as images, videos, or text messages from investigations – for training AI algorithms. Data protectionists sharply criticize this, as AI models often allow conclusions to be drawn about the training data, and the purpose limitation of the originally collected data is greatly extended here.

Options for deprivation of liberty are also increasing. With the revised paragraph 33, the maximum duration of so-called preventive detention is extended from 48 hours to up to five days. In the case of imminent terrorist offenses, up to seven days are even possible. Politically, this tightening was discussed particularly in the context of the actions of the "Last Generation."

The opposition reacted with sharp rejection. They accuse Schwarz-Rot of carelessly sacrificing fundamental rights. Niklas Schrader (Die Linke) spoke of a "black day for civil liberties" in the debate. Vasili Franco (Greens) considers the amendment to be constitutionally highly risky. The Alliance NoASOG views the reform as an attack on civil society. The Society for Civil Rights (GFF) has announced that it will examine a constitutional complaint.

With this decision, Berlin joins the ranks of federal states that have massively tightened their police laws. However, the combination of the new instruments makes the Berlin package particularly far-reaching. The legislator has thus significantly lowered the hurdles for state access to digital and physical privacy. Berlin's data protection officer Meike Kamp described the legalization of the state trojan as a frontal attack on the IT security of all citizens in advance. She saw the sum of the measures as achieving a constitutionally highly questionable density of surveillance.