Federal Constitutional Court sets clear guidelines for law firm searches

When a public prosecutor searches a lawyer’s office, this affects not only the professional concerned but also the interests of uninvolved clients. Every file, email inbox and data carrier may contain highly sensitive information that comes within reach of state investigative measures. The Federal Constitutional Court (Bundesverfassungsgericht, BVerfG) has now clarified that such interventions may only take place under the strictest conditions.

Initial case

A lawyer entered into a fee dispute with a former client. In the course of that dispute, a suspicion of attempted procedural fraud arose, based solely on statements by a former employee of the law firm. A local court subsequently ordered a search of the law firm; among other items, a computer and files were seized. It later transpired that the suspicions were unfounded. The lawyer challenged the search unsuccessfully and ultimately lodged a constitutional complaint with the BVerfG, invoking violations of Article 13 of the Basic Law (inviolability of the home) and Article 103 of the Basic Law (right to be heard).

Decision of the BVerfG

The BVerfG declared the constitutional complaint inadmissible because the lawyer had not exhausted the available legal remedies – specifically, no objection based on denial of the right to be heard had been raised. Nonetheless, the Court used the opportunity to reiterate the standards governing searches of persons subject to professional secrecy.

• First, law firm premises and data are subject to a special need for protection, because investigative measures may incidentally affect completely uninvolved clients and their confidential information. 
• Second, strict proportionality applies: investigating authorities must demonstrate that a search is the least intrusive means, and in many cases targeted requests for the voluntary surrender of information or inspection of specified documents will suffice. 
• Third, every measure requires careful, individualized reasoning; generic justifications are inadequate. In the present case, the Court indicated that the original search warrant did not meet the standard of careful consideration.

Background: No general “legal privilege” under German law

The fact that law firm searches are not per se excluded reflects that German criminal procedure law does not recognize a general, all-encompassing “legal privilege” shielding all lawyer-client communications. Section 160a of the Code of Criminal Procedure (StPO) provides qualified protections against investigative measures directed at attorneys; however, the scope and exceptions are differentiated. In particular, an absolute prohibition on search and seizure applies to defense correspondence in ongoing criminal proceedings, but no blanket privilege extends to all attorney communications in non-defense contexts (see Update Compliance No. 9/2018).

Signal from Karlsruhe to investigating authorities

Even though the BVerfG could not decide the case on the merits, the decision sends a clear message: searches of law firms must remain exceptional. Going forward, investigating authorities must examine and document the necessity and proportionality of searches involving attorneys with particular care. Where searches are conducted, heightened safeguards apply to protect the confidentiality of uninvolved clients.

Protection of unaffected client files remains limited in practice

If the conditions for a search are met, investigating officers may, within the framework of review under Section 110 StPO, access and examine records to identify relevant evidence, which can reach materials of uninvolved clients. It would have been desirable for the BVerfG to clarify that non-relevant client documents should be excluded from review ab initio under Section 110 StPO – at least absent indications that relevant evidence is being hidden within unrelated files. The Court also did not address whether documents of uninvolved clients that come into the hands of investigators as incidental findings may be used under Section 108 StPO. In light of the heightened level of protection required for legal professionals, there are cogent arguments against the admissibility of such evidence.

Implications for companies

Clients cannot rely on a general legal privilege shielding all communications with their lawyers from seizure. However, where clients are not themselves suspects, a high standard of protection applies: investigating authorities may not direct measures at uninvolved clients, and targeted searches for incidental findings are impermissible. Nevertheless, the decision reinforces that authorities must not interfere lightly with confidential client documents stored by law firms.

Recommendations for practice

Lawyers affected by a search must ensure that files of uninvolved clients are not reviewed within the meaning of Section 110 StPO, thereby avoiding incidental findings under Section 108 StPO. Reference should be made to the BVerfG’s standards, and where appropriate, files requested for review should be sealed and a judicial decision obtained. Professionally mandated separate file management facilitates the clear distinction between potentially evidentiary materials and unrelated client documents.

Conclusion

The BVerfG underscores that law firm searches are an extreme measure and must be confined to exceptional cases, with strict adherence to necessity, proportionality and individualized justification. For companies and clients, the decision signals strengthened protection of sensitive data and reaffirms the special safeguards attaching to the legal profession. During any search, special care must be taken to prevent the examination of files of uninvolved clients in accordance with Section 110 StPO.