Villains of the drama await punishment ... or reprieve

When the credit crunch started, it began with fraud – the selling of usurious home loans to people who had no chance of paying them back. In America, agents from the FBI are bursting into small mortgage offices on the edge of hick towns and making arrests.

Some of the cases coming to light are darkly comic – such as the 25-year mortgage sold to an 84-year-old man with Alzheimer's. If the bank executives knew this fraud was occurring they turned a blind eye – the commissions were good and the housing market was rising, so why worry?

The sub-prime mortgage reps can expect a fair trial, then jail. Higher up the chain, lawsuits are emerging which demand to know what bank executives knew.

In the US, these executives will be the subject of lawsuits from investors that might go to court, or be settled. In the UK, bank bosses are more likely to face a roasting by the Treasury select committee.

At a hearing in December, committee chairman John McFall asked executives from Deutsche Bank, Goldman Sachs and UBS to explain how the complex financial instruments the banks sold to investors around the world worked. None could. Asked to define a collateralised debt obligation, Lord Aldington of Deutsche told MPs: "I have not come before this committee as an expert on CDOs."

Many of the maths experts who devised these investments have lost their jobs – to be re-hired when the next boom begins.

The search for who else is to blame will last years but a few candidates include: the bosses of every investment bank including Dick Fuld at Lehman Brothers and John Mack at Morgan Stanley, and in the UK, bankers such as Sir Fred Goodwin at Royal Bank of Scotland. Former Federal Reserve chief Alan Greenspan and Gordon Brown stand accused of failing to stop the housing bubble inflating. Greenspan's reputation is in tatters and Brown may pay with the loss of his job as Prime Minister.