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By Huw Jones and Jamie McGeever
LONDON, March 15 (Reuters) - Britain's fraud watchdog hasended an investigation into possible foreign exchange marketrigging, saying it did not have enough evidence to secureconvictions, in a further setback to its efforts to prosecutewrongdoers in financial markets.
Some of the world's biggest banks have been fined billionsof dollars for trying to manipulate foreign exchange rates aftera global probe into the $5 trillion a day market.
So far no individual traders have not been prosecuted.
The investigation by the Serious Fraud Office began in July2014 after material was passed to it by Britain's FinancialConduct Authority. The SFO was one of several authorities aroundthe world to investigate alleged forex market manipulation. Aninquiry by the U.S. Department of Justice is continuing.
The investigation by the Serious Fraud Office began in July2014 after material was passed to it by Britain's FinancialConduct Authority. The SFO was conducting one of several probesaround the world into the alleged forex market manipulation.
The SFO said on Tuesday that based on the information andmaterial obtained, there was insufficient evidence for arealistic prospect of conviction.
The SFO, which investigates and prosecutes major andmulti-national fraud, bribery and corruption, said its decisionfollowed an independent investigation lasting more than one anda half years and involving over half a million documents.
It said it continued to liaise with the DOJ over its ongoinginvestigation.
The SFO's decision follows the acquittal earlier this yearin a trial brought by the SFO of six former brokers accused ofconspiring with Tom Hayes to manipulate the Libor benchmarkinterest rate.
Hayes was found guilty last August of conspiring to rigLibor and was jailed.
"Coming hot on the heels of the recent Libor verdict thiswill be embarrassing for the SFO," Alison McHaffie, a regulatorypartner with law firm CMS, said.
"However it does show the difficult job the SFO has indemonstrating criminal activity by individuals for this type ofmarket misconduct."
Authorities were first alerted to alleged collusion betweencurrency traders setting benchmark exchange rates at the 4:00 pmdaily "London fixing" in mid-2013.
The subsequent investigations by regulators around theworld, principally in the United States and Britain, led todozens of traders being suspended or fired, new codes of conductdrawn up and some of the world's biggest banks fined more than$10 billion collectively.
The probes centred largely on millions of electronicchatroom communications between groups of FX traders at bankswho routinely shared intelligence on orders they were about toplace for clients.
Many of the traders who were fired during the investigationare now suing their former employers for unfair dismissal. PerryStimpson won his case against Citi in London last November.
Ben Rose, a partner at law firm Hickman and Rose, said theSFO's decision suggested it was pulling back from prosecutingcases linked to financial benchmarks.
"This decision follows the sweeping acquittals of sixbrokers in the recent Libor trial. It suggests that the SFO islosing its appetite for risk and that the Hayes verdict may bethe high water mark for these prosecutions." (Reporting by Huw Jones and Jamie McGeever; Editing by CarolynCohn and Jane Merriman)
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