Things just got worse for HSBC: Here's what you need to know

Things just got worse for HSBC.

Its private banking arm faces new criminal charges after a French magistrate officially requested that the Swiss bank be brought to trial over a suspected tax-dodging scheme for wealthy customers, the Guardian reports.

The request for trial comes after a series of allegations against the bank that date back to 2008, when former HSBC employee Herve Falciani handed over thousands of confidential files from the bank to French tax authorities.

Here's what you need know about the scandal so far:

• HSBC Private Banking is the Swiss banking arm of the parent bank HSBC, which is based in London. HSBC Private Banking is based in Geneva and it is the branch for ultra-wealthy international costumers.
• HSBC Private Banking already faces 10 different enquiries around the world. The alleged tax-dodging scheme is being investigated in eight different countries; Argentina, Brazil, Mexico, Denmark, Belgium, France, India and Switzerland.
• The investigations started in France because Falciani initially leaked data from 100,000 bank accounts to the country's government. Leaking banking secrets is a crime in Switzerland, and Falciani faces prosecution in Geneva. He is currently being protected by the French tax authorities. He also alleged that several agents of foreign secret agencies were also involved in the operation.
• HSBC Private Banking offices in Geneva were raided by the Swiss police on February, 18, for "suspected aggravated money laundering."
• According to Le Monde, the tax evasion scheme involved more than 8,000 French citizens. HSBC refused a plea deal that would have avoided a trial. Under that deal, HSBC would have had to pay €1.4 billion (£1 billion) to be cleared of accusations.
• HSBC admitted the wrongdoings, which refer to the period until 2007, in February this year. It claimed it has now cleaned its operations, stating that "standards of due diligence were significantly lower than today."

The scandal has particular political interest in the UK. HSBC Chairman Douglas Flint and CEO Stuart Gulliver were interrogated by the Treasury Select Committee in the House of Commons on February 25.

Stephen Green, Chairman of HSBC during the period of the accusations, was Minister of State for Trade and Investments from 2011 to 2013 and is currently a Lord for the Conservatives.

Gulliver called the Swiss Private Banking unit "a source of shame and reputational damage" in the past, but he had to answer why he used to own a secret Swiss bank account that allowed him to shelter £5 million ($7.35 million) through a company based in Panama.

Gulliver admitted the account "looked strange," but claimed the account was used to keep his paychecks hidden from other employers at HSBC.

Tax authorities in France, Spain, and the UK have already collected more than £500 million ($735 million) from Swiss accounts at HSBC, but the total assets disclosed by Falciani are worth £78 billion ($114 billion).

HSBC now has one month to reply to the accusations in France, after which the French magistrates will decide whether to proceed with a trial.