Hello, I'm Leslie Cohen, and for the BBC World Service, this is a bad business.

And let's start with an experience which is all too familiar to me.

Oh, we tried bullying me, Jeff Skelling yelled at me on the phone and told me that I was

unethical for raising questions because he said if I had done my homework I would understand

how stupid these questions I was asking were and that it was unethical to raise questions

like this without understanding what you were talking about, which is a scary thing for

a journalist to be told.

That takes me back 20 years.

When I, too, experienced that type of behaviour from Jeff Skelling, chief executive of the

giant energy trader, Enron, who told me off for getting my facts wrong when I hadn't,

the journalist we heard, Bethany McLean, was right to question Enron's accounts.

It collapsed amid huge losses.

I've been covering frauds for 30 years, including Enron, which was the most memorable of the lot.

Over the next hour, I'll be looking at big corporate frauds and accounting scandals, trying

to work out what makes the fraudsters do it, how likely they are to get caught cooking

the books and whether the hard lessons of Enron were ever learned.

This is a bad business.

If we don't help people accountable for really fouling up, where are we headed as a society?

So you think if a crime is committed, what you don't expect is the closing of ranks

right across the board of everybody saying to you, no, no, no, you're just completely wrong.

People think accounting is a science with one specific answer and it's not.

It's art and it's a language and it can be manipulated and it involves judgment calls.

...