Mr Pieth thinks about half of the 30 biggest German and French firms are being investigated or prosecuted for bribing foreign officials.

ECONOMIST: The Siemens scandal

Mark Pieth is professor of criminal law at the University of Basel, Switzerland, and chair of the OECD Working Group on Bribery.

FORBES: Magazine Article

Mark Pieth, the chairman of an OECD working group on bribery, warns that British firms might face international sanctions if the delays continue.

ECONOMIST: Corporate misbehaviour

While there was "welcome" evidence of progress in some areas, Mark Pieth - chairman of the OECD's working group on bribery - said current laws were not adequate.

BBC: UK under fire over bribery laws

From there, a banker with no apparent connection to bin Laden might deposit the money in an offshore account or with an intermediary that specializes in "tax optimization, " explains Pieth.

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