Swiss police arrested ex-banker Rudolf Elmer on Wednesday for giving data to Wikileaks, hours after he was found guilty of breaching strict Swiss bank secrecy laws in another case.
At 1830 (1730 GMT) Elmer was taken into custody by police, having just been found guilty of breaching strict banking secrecy for publicizing private client data and of threatening an employee at his former firm Julius Baer.
The state prosecutor's office is checking to see whether Rudolf Elmer has violated Swiss banking law by handing the CD over to WikiLeaks, the Zurich cantonal (state) police and state prosecutor said in a joint statement.
They declined to give further details.
At a news conference in London on Monday, Elmer handed over data on hundreds of offshore bank account holders to WikiLeaks founder Julian Assange, saying he wanted to draw attention to financial abuses.
WikiLeaks has angered U.S. authorities by publishing hundreds of secret diplomatic cables.
The court had sentenced Elmer to a fine of 7,200 Swiss francs ($7,505), suspended for two years, without giving reasons as they will come in a written judgment. The prosecution had demanded eight months jail and a fine of 2,000 francs.
Wednesday's court ruling did not concern WikiLeaks and the defense will decide whether to appeal within 10 days.
Judge Sebastian Aeppli acquitted Rudolf Elmer on charges he sought $50,000 for returning client data to former employer Julius Baer and that he made a bomb threat to the bank's headquarters.
Elmer, who helped bring WikiLeaks to prominence three years ago when he used it to publish secret client details, had admitted sending Julius Baer data to tax authorities.
But he had denied blackmail and a bomb threat against Julius Baer and said he never took payments in return for secret data.
Elmer spent a month in investigative custody in 2005 when the charges were first made against him.
I am a critic of the system and want to tell society what happens in these murky oases, Elmer, who ran the Cayman Islands branch of the Swiss bank dedicated to wealthy clients until he was fired in 2002, told a news conference before the verdict.
Elmer said Baer waged a campaign of psychoterror against him and his family and offered him 500,000 francs to keep quiet. He said he had never taken payments in return for secret data.
But he admitted writing anonymous emails in 2005 threatening to send client details to tax authorities and the media if Julius Baer did not stop unspecified actions.
The situation was very threatening. We were very scared and I thought the bank was behind it. That is why I sent the emails, Elmer told the court.
Elmer also admitted charges that he sent client details to Swiss tax authorities, but he denied threats against former colleagues.
Julius Baer, which has denied its Cayman branch was used for tax dodging, says Elmer waged a campaign of personal intimidation and vendetta against the bank after it refused his demands for financial compensation following his 2002 dismissal.
We have supported the prosecution, the judge largely followed the prosecutor's argument, said Kurt Langhard, a lawyer for Julius Baer. We are satisfied.
Speaking in court, Prosecutor Alexandra Bergmann said Elmer had cultivated the image of whistleblower only later in his dispute with Baer.
While he was working on the Cayman Islands he didn't question the system as such, Bergmann said.
Elmer's lawyer Ganden Tethong Blattner said her client and his family had paid for standing up to a powerful opponent.
This is the story of a man who discovered misdeeds and was under constant surveillance for more than a year. This great pressure was aimed at silencing him, she said.
About a dozen protesters from the left-wing Alternative Liste party had gathered outside the court, holding up a banner, saying: They want to hang Rudi, they let Kaspar off the hook, in a reference to UBS chairman Kaspar Villiger.
Switzerland last year gave details of about 4,450 UBS accounts to U.S. authorities as part of a deal to settle a tax probe into its biggest bank despite strict secrecy laws. None of its bankers were prosecuted in Switzerland.
Elmer, a certified auditor who also worked at Credit Suisse and KPMG, had argued Swiss bank secrecy should not apply, since the documents he leaked referred to accounts in Cayman.
Swiss bank secrecy has come under global attack in recent years, with neighboring Germany buying secret data from informants in a bid to track down tax evaders.
(Additional reporting by Martin de Sa'Pinto and Andrew Thompson; editing by Philippa Fletcher)