The UBS trader accused of fixing LIBOR was nicknamed 'The Rainman'

The former UBS and Citi trader standing trial for rigging LIBOR was nicknamed "The Rainman" and "Tommy Chocolate" by friends - and had a superhero duvet on his bed until he was 24.

The snippets of Tom Hayes' personal life came to light in the first day of his defence on Tuesday at Southwark Crown Court in London.

Hayes is accused of rigging LIBOR - the London Interbank Offered Rate. The daily measure is meant to show the rate at which banks will lend to each other and is used to set the price of trillions of dollars worth of financial products. Hayes and other traders allegedly manipulated the rate to benefit trades they were carrying out.

Hayes suffers from mild Asperger's Syndrome and told the court he was given the nickname "The Rainman" by a former Royal Bank of Scotland trader "basically because I was different," the FT reports.

Hayes said: "I didn't get a lot of jokes and I had the same superhero duvet cover that I had when I was 8 when I was 24."

The 1988 film The Rainman starred Dustin Hoffman as an autistic savant whose brother exploits his ability to count cards.

Hayes' "Tommy Chocolate" nickname came from the fact that he didn't drink pints of beer when he went with colleagues to the pub at lunch times - instead opting for a hot chocolate.

As part of his defence Hayes repeated his assertion that top management knew exactly what he was doing. He Hayes told the jury: "Everything I did was with complete transparency. Everything I did my managers knew about?.?.?.?sometimes going up all the way to the CEO."

Hayes doesn't specify which CEO he's talking about. He's standing trial for 8 counts of conspiracy to defraud covering the period 2006-2010, during which he worked at both UBS and Citi.

The BBC reports that Hayes testified that senior managers at UBS discussed fixing LIBOR and "nobody batted an eyelid."

The court has already heard tapes of Hayes telling the Serious Fraud Office that managers at UBS told him to fix LIBOR.

He told the court that traders at UBS seemed to be fixing LIBOR before he arrived, but when he moved to Citi lawyers began to question his methods.

While banks have been fined for the scandal, Hayes is the first person to stand trial for fixing the rate. He confessed to the Serious Fraud Office that he did it but in his defence today said this was just to avoid extradition to the US.

The case continues.

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