HSBC's Swiss private bank helped hide millions of dollars for drug traffickers, arms dealers and celebrities as it assisted wealthy people around the world in dodging taxes, according to a report based on leaked documents that lifts the veil on the country's banking secrecy laws.
The report from the International Consortium of Investigative Journalists and several news organizations comes as governments seek to crack down on tax evasion to bolster treasuries depleted by the financial crisis and staunch criticism that the rich aren't paying their fair share.
The leaked documents cover the period up to 2007 and relate to accounts worth about $100 billion held by more than 100,000 people and legal entities from 200 countries.
Some details of such operations were disclosed previously, when HSBC was fined by the U.S. in 2012 for allowing criminals to use its branches for money laundering. Monday's report discloses a more detailed cache of data and information.
Academics estimate that $7.6 trillion is held in overseas tax havens, depriving governments of approximately $200 billion a year in tax revenue, according to the ICIJ report.
The French government received the files from a whistle-blower in 2010 and passed them on to tax authorities around the world, including those in the U.S., Britain and Germany.
In Britain, where HSBC is based, the report sparked criticism that tax authorities hadn't done more to penalize people who have illegally evaded taxes. The tax agency clawed back about $236 million from some of the 3,600 Britons identified as using the Geneva branch of HSBC, but only one has been prosecuted.
France, by contrast, launched 103 actions. French Prime Minister Manuel Valls told Europe 1 radio on Monday that France is "very determined" to fight tax evasion and will continue to take action at home and at the European level.
In Britain, lawmakers reacted with outrage.
"You are left wondering, as you see the enormity of what has been going on, what it actually takes to bring a tax cheat to court," Margaret Hodge, chair of Parliament's Public Accounts Committee, told the BBC.
Hodge also said the former chairman of HSBC, Stephen Green, who became the government's trade minister after he left the bank in 2010, must face serious questions about whether he was "asleep at the wheel, or he did know and he was therefore involved in dodgy tax practices."
HSBC stressed that the documents were from eight years ago, and said that it has since implemented numerous initiatives designed to prevent its banking services from being used to evade taxes or launder money.
Franco Morra, chief executive of HSBC's Swiss subsidiary, said that the new management had overhauled the business and shut down accounts from clients who "did not meet our high standards."
"These disclosures about historical business practices are a reminder that the old business model of Swiss private banking is no longer acceptable," he said in a statement.