A whistleblower from Barclays Bank makes the obvious point that former CEO Bob Diamond had to know about the various fixings of the Libor benchmark inter-bank lending rate before he claims to have found out:

Speaking on condition of anonymity, the banker says that senior Barclays bosses would have been told about Libor concerns because staff were drilled to pass anything untoward up to their managers. Failure to do this meant the sack.

“Libor fixing was escalated by several people up to their directors, they would then have escalated it up the line because at Barclays if you don’t escalate, and it is found out that you haven’t, it is grounds for disciplinary action. You will be dismissed.”

The banker also describes the dark side of working for Mr Diamond’s bank. He spoke of management by intimidation, even physical threat, punishing hours and a ruthless grading system that left workers in terror of their annual appraisals. Employees were often reduced to tears by the end of a day, but only when they had departed from the building. Such weakness would not be tolerated inside.

Diamond’s testimony before Parliament never made any sense. He claimed simultaneously that he just found out about the seriousness of the Libor rigging, and that he held a conversation with the Bank of England’s top officials in 2008 that Barclays Libor submissions were coming in on the high end, with a wink-and-a-nod encouragement to lower those numbers. These two things cannot be true at the same time. And the anonymous banker simply reinforced this, through his explanation of the corporate culture, and how word would have gotten to the senior managers quickly.

Paul Tucker, deputy governor of the Bank England, testifies before Parliament this week, and we should get more understanding of that meeting between him and Diamond, where Barclays’ Libor rates were discussed. If it does come out that the central bank in England advised a major bank to fix their inter-bank lending rate to mask their dodgy performance, this becomes a much bigger scandal.

The anonymous whistleblower, meanwhile, told his story in his own words here. He states that the culture of greed and favor-granting ultimately came from Diamond himself. This is the latest in a long line of testimonials about the diminished and rotting culture of the financial sector. I’m not sure I buy that there was some Golden Age of banking, but this former employee offers a rich description of a company ruled by fear, where corner-cutting and profit-at-all-cost decision-making was enforced by the fear of losing your job or your bonus.

The whistleblower basically says that they first noticed the spread in the Libor rates, between what Barclays paid for borrowing and what rates were being posted, in 2008. And if he knew, senior executives all the way up the chain knew. So Diamond lied to Parliament.

And if the result of the fixings are tens of billions in losses by local governments which entered into interest rate-swap deals, then this lie takes on a new resonance.