In a judgment dated December 23rd, 2003, the Swiss Federal Supreme Court (hereafter "SSC") (www.bger.ch) clarified the rules governing international mutual legal assistance in criminal matters, and in particular clarified the principle of proportionality which constitutes a limit to the transmission of evidence taken in Switzerland to a Requesting State. SSC decision 23.12.2003, case 1A.223/2003.

This judgment will put an end to the Swiss authorities current practice of transmitting documents to the requesting state without a prior detailed screening of said documents.

After analysing the application of the principle of proportionality with regard to the transmission of documents (in particular banking documentation) in cases of international mutual assistance in criminal matters, the SSC found that certain Swiss federal and cantonal authorities were violating said principle (Section 1). The SSC then proceeded to clarify the duties and obligations of the Swiss authorities whose assistance had been requested by a foreign state (Section 2).

1. The Prior Swiss Practice

The principle of proportionality applied to international mutual legal assistance implies that the assistance sought must be necessary in proceedings which serve as the basis for the request. It is also undisputed that the requested governmental authority must narrowly tailor their response and not provide more than the Requesting State has requested. BGE 115 Ib 373.

These clear principles were nevertheless limited in scope based on the so-called "potential relevance" theory developed by the SSC in a previous case. BGE 121 II 241. The consequences of this limited application of the principle of proportionality is crystallized in the "Guideline for International Mutual Assistance in Criminal Matters" developed by the Swiss Federal Office of Justice (www.ofj.admin.ch), which states that "the deciding factor is the potential relevance: only those papers which are definitively not of relevance for the foreign criminal proceedings are not to be sent abroad".

Based on the above-principles, the Swiss federal and cantonal authorities adopted a controversial practice under which these authorities would consider that the whole of the documentation obtained could be transferred to the Requesting State provided that: (i) they seemed potentially relevant to the facts related in the request; and (ii) so long as the holder of the requested documents did not provide to the authorities a document by document specific and detailed objection that would justify the refusal to transmit.

2. Newly Defined Duties of Swiss Authorities

The judgment rendered on December 23rd, 2003 specified that the above practice violated the principle of proportionality and it instructed the Swiss Federal Office of Justice to remind the federal and cantonal authorities that the following basic rules should be followed:

After seizing the documentation that it believes to be relevant under the assistance request, the Swiss authority must fully screen the documents it intends to transfer to the requesting State;

  • In order to avoid unnecessary damages to the holder of said documentation, this screening must be completed shortly after seizing the documents;
  • The Swiss authority may complete the detailed screen with the help of the requesting foreign magistrate (official) and with the assistance of the holder of the documents;
  • Should the transmission of the documents be contested by the holder, the Swiss authority must fix a deadline under which the holder must present his document by document arguments opposing said transmission;
  • Finally, the requested authority must render a detailed decision setting forth its findings in cases that are contested.

The fact that the holder does not present his arguments or does so incompletely does not waive the requested authority’s obligation to screen the documents as imposed by the principle of proportionality.

The Swiss authorities in charge of international mutual assistance in criminal matters are therefore always obliged to fully screen the documents intended for transmission. This decision will unquestionably reinforce the effectiveness of Swiss banking secrecy in legitimate cases, i.e. where no criminal activity from the Swiss point of view is involved (for additional information on the Swiss banking secrecy please refer to the "Publications" section at www.secretantroyanov.com).

This article has been prepared by Secretan Troyanov for informational purposes only and is not legal advice. Transmission of the information is not intended to create, and receipt does not constitute, an attorney-client relationship. Readers of this article should not act upon this information without seeking professional legal advice applicable to their specific circumstances.