ZURICH (Reuters) - Swiss banker Rudolf Elmer, among the first to use WikiLeaks to publish private bank documents, goes on trial Wednesday charged with breaching banking secrecy and threatening his former employer.

The former Julius Baer executive is accused of making threats to the bank’s personnel, including a bomb threat, and seeking cash in return for secret bank data, and also faces charges of breaching bank and corporate secrecy.

Prosecutors are asking for Elmer, who headed Baer’s office in the Cayman Islands until he was fired by the bank in 2002, to be sentenced to an eight-month jail term and a 2,000 Swiss franc ($2,083) fine. The hearing is expected to last just one day.

Wednesday’s case does not concern his publication on WikiLeaks, but earlier alleged breaches of bank and corporate secrecy in Switzerland.

Elmer, a certified auditor who also worked at Credit Suisse and KPMG, said he did not breach Swiss bank secrecy, since the documents he leaked referred to accounts in Cayman, where Swiss courts have no jurisdiction.

Monday, the banker handed over compact discs he said contained information on some 2,000 offshore banking clients to WikiLeaks founder Julian Assange at a media event in London.

Elmer helped put WikiLeaks in the spotlight after he used the site to leak secret data, prompting Julius Baer to launch a lawsuit against the website in 2008. It later dropped its bid to block the site after an outcry from free-speech advocates.

He said he took his information to the website after Swiss authorities failed to act on it.

RECIPROCAL ACCUSATIONS

Elmer, 55, accuses Baer of waging a campaign of persecution against him and his family, and of offering to pay 500,000 francs for his silence.

Julius Baer says that Elmer waged a “personal intimidation campaign and vendetta” and sought to discredit the bank and its customers after it refused his demands for financial compensation following his dismissal.

Swiss lawyer Valentin Landmann, who recently made an unsuccessful appeal against the conviction of two other Swiss whistleblowers, said Elmer’s case would turn on his intent.

“A lot could depend on whether the whistleblower is seen as acting altruistically or is motivated by profit,” he said.

“The court will want to establish a clear insight into the moral intent, which must be proper if people wish to disclose something which they cannot disclose through the normal channels,” Landmann said.

Swiss bank secrecy has come under global attack in recent years, with neighboring Germany buying secret data from informants in its bid to track down tax evaders.

Switzerland was also forced last year to hand over details of about 4,450 bank accounts to U.S. authorities as part of a deal to settle a tax probe into the U.S. clients of its largest bank, UBS.

Another whistleblower, Bradley Birkenfeld, who helped expose widespread tax evasion involving UBS’s wealthy American clients, is currently serving a 40-month prison term in Pennsylvania’s federal prison for his role in setting up those accounts.