On August 19 2016 the Zurich Supreme Court rendered a long-awaited decision regarding a former Swiss banker who between 1994 and 2002 worked as head of accounting and later as general manager of a bank and trust entity operated by a major Swiss bank on the Cayman Islands.

In 2005 the former banker gave a CD containing 169 megabytes of bank client data to the media. In January 2011 he held a press conference in London where he handed over two CDs reportedly containing bank data for 2,000 clients to Wikileaks founder Julian Assange, for which he was arrested and held in investigative custody for 30 days.

In January 2001 the Zurich Lower Criminal Court convicted the former banker of coercion and necessitation of his former employer (since he had previously threatened to inform the media), as well as for repeated violations of Swiss bank secrecy laws. The court also denied the former banker's allegations that he had acted as a whistleblower.

In August 2016 the Zurich Supreme Court held that Swiss bank secrecy laws had not been violated, as the former banker had been employed by the Cayman Islands bank and trust entity operated by the Swiss bank (ie, the parties had concluded an employment contract under local laws). Conversely, an expatriate agreement with the Swiss bank parent – which regulated the bank manager's Cayman Island assignment between 1999 to 2002 – was not a valid argument for continuing employment under Swiss banking law, as it covered only the employee's social security and pension fund.

Both courts were unwilling to accept the former banker's defence that that he had acted as a whistleblower. The courts concluded that the banker had acted primarily out of disappointment and humiliation due to his allegedly wrongful dismissal by the Cayman Islands bank in 2012, and not primarily because he had wanted to expose the potential abuses of the offshore structure entertained by Swiss banks in general.

The decision is subject to appeal before the Swiss Supreme Court in Lausanne. Both the state prosecutors and former bank manager have indicated that they will call on the Swiss Supreme Court for a final review of the case. The state prosecutors wish to see a conviction for violation of Swiss banking secrets, while the former banker still maintains that he acted as a legitimate whistleblower.

For further information on this topic please contact Thomas Rihm at Rihm Rechtsanwälte by telephone (+41 44 377 77 20) or email (thomas.rihm@rihm-law.ch). The Rihm Rechtsanwälte website can be accessed at www.rihm-law.ch.

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