Ex-Barclays traders are using bullying as a defence in a LIBOR rigging trial

Five former Barclays traders on trial for manipulating the LIBOR interest rate benchmark are giving their defence in London this week and several are blaming a bullying culture in the office for their actions, according to the Financial Times.

The FT reports that Jonathan Mathew testified that his boss used to call him a "deaf git" and "humiliate" him by "whacking" him with a baseball bat. He and four others are charged with manipulating LIBOR for 2 years up to 2007.

Similar allegations have already been reported by multiple newspapers including the Daily Mail and The Telegraph. Both reported that Peter Johnson make Mathew, who is partially deaf and dyslexic, stand on a chair and recite world capitals, as well as taunt him with names and the 12-inch baseball bat. Johnson, who has already pleaded guilty to fixing LIBOR, was the main LIBOR submitter at Barclays.

LIBOR stands for the "London interbank offered rate" and is a measure of what interest rate banks would lend to each other at. While it may sound like an obscure high finance instrument, it is used to set the price of trillions of dollars of products.

The FT reports that another former Barclays trader, Alex Pabon, was close to tears when he testified at Southwark Crown Court this week, saying: "You definitely follow instructions from your boss... I was kind of burnt out and ready to leave."

The 12-week case continues.