By Estelle Shirbon
LONDON (Reuters) - Bank of England officials and a trade organisation in charge of benchmark interest rates were concerned about the integrity of the rate setting system as far back as 2007, according to evidence disclosed on Friday at the trial of a former trader accused of rate rigging.
But a witness from the trade body said the concerns were over banks distorting the Libor benchmark system during the 2007-2008 credit crunch to allay solvency fears, not about traders manipulating rates to benefit their specific positions.
Interest rates known as Libor are under scrutiny at the trial of Tom Hayes, a former yen derivatives trader at UBS and Citigroup (NYSE:C), who is accused of conspiring with others to rig the rates between 2006 and 2010 to increase his trading profits.
Hayes has pleaded not guilty to eight counts of conspiracy to defraud. His lawyers will set out a detailed defence later in the trial, which is scheduled to last into August.
The London interbank offered rate or Libor is used to price an estimated $450 trillion (294.62 trillion) of financial contracts worldwide. It is calculated through an "honour system" in which a panel of banks submit their estimated costs of borrowing from each other in different currencies.
A former Libor manager at the British Bankers' Association (BBA) trade body, which oversaw Libor at the time, told the court that in 2007-2008 there were growing concerns about banks making unrealistically low submissions.
John Ewan said the practice, known as lowballing, aimed to flatter banks' credit-worthiness at a time when credit was fast drying up in interbank money markets.
"Before, it (Libor) had been a very minor cog in global financial markets. Now, it became used very widely as an indicator of stress," he said, adding this had made it difficult to operate the Libor system as it had been intended.
"MEGA PROBS"
Prosecutors allege that Hayes used a network of brokers and traders to put pressure on banks' Libor submitters to raise or lower their numbers to benefit his trading positions.
Ewan differentiated such practices from lowballing and said he was unaware of them until 2012, when U.S. regulators fined Barclays (LONDON:BARC) in relation to that form of Libor-rigging.
Ewan said prior to that he did not think Libor submitters within banks would tailor their figures to the needs of a particular trader as the banks in their entirety were both lenders and borrowers so others within them would lose out.
The jury at Southwark Crown Court were shown emails sent by Ewan and others in 2007-2008 that showed concerns about Libor.
"I am starting to receive more and more comments and queries on the levels at which rates are currently setting," wrote Ewan, who now works for Thomson Reuters as head of fixings business development, in an internal email in November 2007.
"I understand that the Bank of England is informally asking questions of market participants and I know that this is an issue in which Paul Tucker is interested," he wrote.
Tucker was the Bank's executive director for markets and also a member of the Monetary Policy Committee (MPC) at the time. He later became deputy governor.
In another email in December 2007, Ewan wrote: "I have heard from two sources that as yet unnamed contributor banks have offered to take U.S. dollars at 10 basis points above the rates submitted to the fixing process earlier in the day. I feel strongly that if this is true it should not be allowed to continue."
The court was also shown email traffic between the BBA and the Bank of England about a paper on Libor governance that the BBA was working on in the spring of 2008.
In a June 2008 email, Ewan passed on to colleagues feedback from the Bank, including that the words "enviable reputation for accuracy" should be removed from passages about Libor.
The jury also saw an internal email sent in May 2008 by Angela Knight, then chief executive of the BBA.
"Any change to Libor will cause mega probs (sic) except at fringes. I do not want to do a consultation ... We need to reinforce Libor not change," she said in the email.
The Libor system has since been changed and the BBA is no longer in charge.