Corporate values & reality

The Global Financial Crisis (#GFC) has shown that some of our 'greatest' companies were no more than fraudsters at worst and incompetent at best.
This made me think about all the corporate value statements that I've seen over the years and what they really mean. And it also made me ask how can we see through the stated values to see the real values enacted as behaviour in a particular company?
For a university assignment a few years ago I took a copy of the Enron corporate values from their 1998 annual report. They are nice values. I would be happy to have a company that used values like these to drive their behaviour. But clearly there was a vast disconnect between the published values and acceptable behaviour in Enron.
I wonder how many companies are like Enron - all squeaky clean on the outside, but rotten on the inside? So many companies are turning out to be whited sepulchres to use a biblical turn of phrase.
But how does someone like me, who is outside the company, get to see the real corporate behaviour? What are the warning signs for ordinary people? How can we trust companies with our lives, our money and our families?
More on this later ...
Source: Yale (opens Word document)