A WEALTHY currency trader from Hampshire has received a boost after appealing against his conviction for defrauding a client out of millions of pounds.

Mark Johnson, former head of HSBC Bank’s foreign exchange cash trading, was jailed for two years after being found guilty of fraud and conspiracy.

The 51-year-old father of six from Burley was also told to pay a fine of $300,000 – £215,000.

Now the ACI Financial Markets Association (ACIFMA), a global trade body representing 9,000 financial market professionals, has vowed to support Johnson, who was convicted following a month-long trial in New York.

ACIFMA is planning to submit a legal document known as an amicus brief.

It will argue that upholding the conviction could spook banks, hike trading costs and have far-reaching implications for foreign exchange markets.

Amicus briefs are filed by third parties with a strong interest in the case and aim to provide the court with extra information that could prove relevant.

As reported in the Daily Echo, Johnson was convicted of nine charges.

He and a colleague were found to have manipulated currency values, making £5.5 million for HSBC – which was not accused of any wrongdoing – at the expense of its client.

Johnson, who owns a £1.8 million mansion in Burley, is a keen rugby player who formerly captained a side at Ellingham and Ringwood Rugby Club.

In 2011 Edinburgh-based Cairn Energy asked HSBC to convert proceeds from the sale of an Indian subsidiary from dollars into pounds.

But Johnson took part in a practice known as “front running”, which involves ramping up the price of sterling in advance of an exchange.

During his trial it was alleged that he and another HSBC executive bought sterling ahead of the deal, inflating the currency’s value and thus forcing Cairn to pay a higher price.

US prosecutors played tape recordings of phone calls, including one in which Johnson said: “I think we got away with it.”

He also discussed how high the pound might go before Cairn would “squeal”, the court heard.

Johnson was found guilty ten months ago.

He became the first person to be convicted in a global crackdown on currency rigging, and was jailed earlier this year.

He was released a few weeks ago after lodging an appeal and is reported to be back in the UK.