US regulator demands 'effective cop' for UK Libor banks
If the financial markets are like the Wild West, and the evidence of recent days certainly suggests they are, then Gary Gensler is the sheriff.
He's the guy who kicked open the door of the saloon where the vast British bank Barclays was carousing with some of the world's other giant financial institutions and - silver badge glinting in the sunlight - slapped it with a $450m (£290m) fine.
Yes, Mr Gensler is in charge of the Commodities and Futures Trading Commission, the US regulator which, back in 2008, initiated the investigation into Barclays' attempts to rig interest rates.
He is in no doubt how serious Barclays' actions have been. "It affects us all," he said. "We all lose."
He added: "Anyone who has a credit card or a student loan or a mortgage, deep buried in the documentation, it might say that it's based upon this rate that's supposed to be the wholesale rate amongst very large banks in London."
It is reckoned that some $350tn of transactions are pegged to Libor, the interest rate Barclays was attempting to rig.
"Attempting to manipulate that rate because a desk somewhere in Barclays wanted to profit, that's a very serious offence," Mr Gensler tells me.
Libor is the "London Interbank Offered Rate" and is - as the name suggests - compiled in London by the British Bankers' Association.
So, a key question in all this is why on earth it took a US regulator to spot a problem in the UK.
Mr Gensler acknowledges that it has put the UK regulatory system in the spotlight.
"I would note the British Bankers' Association is not regulated and it does raise the question about the reliance on self-regulation," he said.
His criticism of the UK regulators is measured but very pointed: "You need an effective cop on the beat. You need common sense rules of the road.
"And here the common sense rule is, there has to be honesty and integrity in these rates that are so critical and central to the markets."
'Need for transition'
But Mr Gensler believes that the problems with Libor are more fundamental even than the fact that banks have been colluding to rig it.
"I think it is critical that such an important rate not be susceptible to manipulation and that the markets have confidence that they're based on real transactions," he said.
What he is getting at is that Libor is supposed to be based on the interest rates banks charge each other to borrow money.
The problem is that during the credit crunch, banks did not want to lend money to each other on any terms.
What that means is that there weren't any loans on which Libor could be based, yet a rate was still published.
Once again Mr Gensler is measured, yet pointed: "There may need to be a transition to a rate that is based upon real transactions, real facts."
That is a very significant statement, coming from the chairman of the key US regulatory body.
The sheriff seems to be saying that it may be time to close down the saloon. This may mark the beginning of the end of Libor itself.