Just when you think things couldn't get any worse at the banks, they do.

With every day that passes, it is clear that the Irish-owned banks are even more bust than we thought they were.

Regardless of what now happens to his companies, property developer Liam Carroll has left the cat out of the bag.

Evidence presented to the High Court in the application by his Zoe group of companies seeking the appointment of an examiner indicates that its properties are worth only a little over a fifth of the €1.2bn it owes the banks.

This means that the loan losses at the six Irish-owned banks are much, much more severe than had previously been thought.

Between them the six Irish-owned banks have a combined loan book of just over €400bn. About €90bn of this is development lending which is destined to go to NAMA when the Dail finally passes the legislation setting up the new "bad bank" next month.

If the Carroll precedent were applied in setting the discount NAMA would receive on these loans it would pay just €20bn, triggering losses of €70bn.

Losses on such a scale would wipe out the capital of the Irish-owned banks, including the €11bn the State has pumped into AIB, Bank of Ireland and Anglo, more than three times over.

Even if NAMA can justify paying more for these loans it is now clear that the banks will receive far less for them than they originally anticipated.

NAMA-induced losses will almost certainly lead to the de facto nationalisation of the Irish-owned banks.

And then there are all of the banks' other loans.

These include about another €60bn of non-development loans to builders and property developers, €150bn of residential mortgages, personal loans, car loans, credit card debt and just about every other species of reckless lending known to God or man.

No matter how you choose to do the numbers, this means that the Irish-owned banks are probably looking at total loan losses of at least €50bn. So far they have admitted to just over €10bn of these losses.

SCHMUCKS

And who is going to foot the bill for these losses?

Yes, you've guessed it.

Schmucks like you and I will be forking out higher taxes well into our dotage to pay for the folly of our bankers.

That's not good enough.

If we are going to have to pay for the mistakes of the bankers then we need answers.

We must learn the lessons of this fiasco so that nothing like this ever happens again. So how do we get these answers?

Economist Colm McCarthy of An Bord Snip Nua fame has proposed a parliamentary inquiry along the lines of the PAC investigation into the DIRT scandal.

This would have the power to compel witnesses to attend hearings and answer questions.

Oh, what I wouldn't give for the sight of our bankers squirming as they are forced to answer the hard questions.

The inquiry would also, like the DIRT investigation before it, have the power to subpoena documents.

Wouldn't we all love to read how our ever-so-smart bankers, who in the good times were never slow to lecture the rest of us on how we should conduct our affairs, justified lending of billions to property developers and speculators who it now transpires don't have two coppers to rub together?

The DIRT inquiry was the most effective public investigation of recent years.

It cost a fraction of what the tribunals have cost and netted several hundred million euro in unpaid taxes for the state.

Unfortunately, an parliamentary investigation of the banking collapse won't get the money back. However, forcing our bankers to admit to their mistakes would be some small consolation.

- Dan White