Court told of trader's boast: give them a Mars bar and they'll fix Libor

The former City trader accused of manipulating the benchmark Libor lending rate admitted having an “explosive” temper but denied he had behaved “unprofessionally” in the market, a court has heard.

An internal bank memo described the behaviour of Tom Hayes in the market as “far from professional” and said some colleagues saw him as an “immature, explosive person regularly losing his temper and constantly threatening to pull broker lines”.

Mr Hayes claimed the unflattering assessment of him by a colleague at the Swiss bank UBS was “inaccurate” and “a lie” he told a jury at Southwark Crown Court.

He admitted losing his temper on occasions but claimed the email was the result of a “massive power battle” between him and a colleague about who could market which financial products offered by the bank. The row was eventually settled by a director at board level, the court was told.

Mr Hayes, 35, from Fleet, in Hampshire, denies eight charges of conspiring to manipulate Libor, a vital bank lending rate which determines the value of financial instruments worth trillions of pounds.

The court heard defence counsel Neil Hawes, QC, suggest that fixing the Libor rate was so commonplace at UBS that it was taking place there before Mr Hayes joined the bank in 2006. Asked in one email whether the rate was artificially fixed, Mr Hayes replied: “Yes, of course they are. Just give the cash desk a Mars bar and they’ll do whatever you want.”

Mr Hayes claimed that obtaining fixes of the rate to benefit the bank’s own trading position was discussed openly. He later told investigators from the Serious Fraud Office the idea it was done “in darkened rooms where everyone whispered” was far from the truth.

Several emails were read out in evidence in which traders and other employers discussed the reasons why they wanted higher or lower Libor rates.

One senior manager, Panagiotis Koutsogiannis, warned a trader in 2008 about discussing fixing Libor rates openly on the bank’s internal chat system. “Just be careful , Dude,” Mr Koutsogiannis, who was known as Pete the Greek, warned.

Warned by his boss Mike Pieri about not mentioning Libor fixes on email, Mr Hayes told the court the only lesson he drew from it was “The message I got was carry on doing it but don’t put it in an email.” Neither Koutsogiannis or Pieri has been accused of wrongdoing.

The case continues.