Raoul Weil, the chairman and CEO of the global wealth management and business banking division at UBS, has been indicted by a federal grand jury on charges that he helped US taxpayers avoid income taxes on assets in overseas accounts.

According to the indictment, Weil and other UBS bankers used encrypted laptops and other counter-surveillance techniques to assist US clients in concealing their identities and nearly $200bn (£135bn) in offshore assets from US authorities.

The indictment claims that Swiss bankers who reported to Weil routinely travelled to the US to discuss Swiss bank accounts with current and prospective clients. Between 2002 and 2007, these activities allegedly generated nearly $200m (£135m) in cross-border business for UBS.

The Am Law Daily reports that Weil is being represented by Aaron Marcu, head of the white-collar defence and investigations practice at Covington & Burling in New York.

"Today's indictment is totally unjustified and without any factual basis," said Marcu. "[Weil] denies any suggestion that he was aware of, engaged in, or tolerated any illegal conduct in the operation of UBS's US cross-border business. That business represented only a tiny percentage of the global wealth management business for which [Weil] is responsible."

The indictment comes in the wake of the scandal surrounding UBS investment banking general counsel David Aufhauser's resignation in August, following allegations of involvement in the bank's alleged sale of auction-rate securities based on inside market knowledge

Aufhauser had been named in a three-man team to temporarily fill group general counsel Peter Kurer's role when Kurer was appointed as the bank's chairman in April.

Swiss Re group legal officer Markus Diethelm was later appointed as the bank's new group general counsel.

Weil, who is not a lawyer, headed the Swiss banking giant's international wealth management unit between 2002 and 2007 and was appointed to the bank's group executive board in July 2005.

The charges against Weil date back to a 12-page indictment that the Justice Department unveiled in May against former UBS private banker Bradley Birkenfeld and the co-founder of a Liechtenstein-based bank. Prosecutors accused the two of aiding American real estate developer Igor Olenicoff in evading income taxes on $200m in assets that he allegedly stashed in offshore accounts.

Birkenfeld pled guilty in June to charges that while at UBS he helped wealthy Americans hide assets in overseas accounts to avoid paying income taxes. Prosecutors have asked that Birkenfeld's sentencing be delayed so as to ensure his continued cooperation with investigators.

UBS said in a statement that Weil will relinquish his current duties at the company in order to defend himself.

The Am Law Daily is the website of The American Lawyer, Legal Week's US sister title.

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