Jury out to consider verdict in world's first Libor-rigging trial

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LONDON, July 27 (Reuters) - The jury in the London trial of former trader Tom Hayes, who is charged with eight counts of conspiracy to defraud by manipulating global Libor interest rates, retired on Monday to consider its verdict after hearing nine weeks of evidence.

Hayes, a 35-year-old former UBS (NYSEArca: FBGX - news) and Citigroup yen derivatives trader based in Tokyo, pleaded not guilty to charges he conspired to rig the London interbank offered rate (Libor), a benchmark for $450 trillion of financial contracts and loans worldwide, between 2006 and 2010.

The Serious Fraud Office (SFO) alleges Hayes set up a network of brokers and traders that spanned 10 of the world's most powerful financial institutions, cajoling and at times bribing them to help rig rates -- designed to reflect the cost of inter-bank borrowing -- for profit.

Hayes, who was diagnosed with mild Asperger's Syndrome just before his trial began, has said he was transparent about trying to influence rates and that his managers were aware of and condoned trading methods that were common industry practice.

He denied dishonesty, said he had received no training, that Libor was at the time unregulated, his requests for higher or lower rates fell within a "permissible" range and he left a trail of emails and computer chats because he did not think he was doing anything wrong.

During 82 hours of interviews with SFO investigators in the months following his arrest in December 2012, Hayes admitted dishonesty. But he told the court this month he only did so to ensure he would be charged in Britain and avoid extradition to the United States, where he also faces fraud-related charges.

Hayes subsequently withdrew from a cooperation agreement with the SFO and in December 2013 pleaded not guilty.

Summing up the case to the 12 jurors in the final days of the trial at Southwark Crown Court, judge Jeremy Cooke told them the central issue they had to decide was whether Hayes had acted dishonestly "by the standards of reasonable, honest members of society".

"Not by the standards of the market in which he operated, if different (from those of reasonable and honest people). Not by the standards of his employers or colleagues, if different. Not by the standards of bankers or brokers in that market ... even if many or even all regarded it as acceptable," the judge said.

He also told them that they should focus on Hayes alone, not on others who might have been involved in rigging Libor.

"Do not concern yourself with others who may or may not be prosecuted, whether or not there was or was not a more general endemic problem in the market at the time of which they were or were not part," he said. (Reporting by Estelle Shirbon, writing by Kirstin Ridley; editing by Stephen Addison)