The attempts to rig LIBOR (the London inter-bank offered rate), a benchmark interest rate, betrays a culture of casual dishonesty amongst bankers who were held in high esteem.

 At present, the scandal rages in one country and around one bank. Barclays has been fined estimated $450m by American and British regulators for its attempts to manipulate LIBOR. Barclays is the first bank in the spotlight because it offered to co-operate fully with regulators. It will not be the last. Investigations into the fixing of LIBOR and other rates are also under way in America, Canada and the EU.

The evidence that has emerged from the Barclays investigation reveals two types of bad behaviour.

The first was designed to manipulate LIBOR to bolster traders’ profits. It appears that Barclays traders pushed their own money-market desks to doctor submissions for LIBOR (and for EURIBOR, a euro-based interest rate put together in Brussels). They also appeared to be colluding with counterparts at other banks, making and receiving requests to pass on to their respective submitters. This bit of the LIBOR scandal looks less like rogue trading, more like a cartel.

The second type of LIBOR-rigging, which started in 2007 with the onset of the credit crunch, could also lead to litigation, but is ethically more complicated, because there was a “public good” of sorts involved. During the crisis, a high LIBOR submission was widely seen as a sign of financial weakness. Barclays lowered its submissions so that it could drop back into the pack of panel banks; it has released evidence that can be interpreted as an implicit nod from the Bank of England (and Whitehall mandarins) to do so. The central bank denies this, but at the time governments were rightly desperate to bolster confidence in banks and keep credit flowing. The suspicion is that at least some banks were submitting low LIBOR estimates with tacit permission from their regulators.

The roll call of alleged malfeasance at other banks is also long. Investigators in Europe, Asia and the U.S. are piecing together a widespread conspiracy by as many as 16 banks to conceal the extent of their problems during the financial crisis — and boost traders’ profits.