What role should CPA's play in capital markets?

Given the much less recent but still mentionable cases of accounting fraud at Enron and WorldComm it seems reasonable to ask what do accountants really do these days? I open the wall street journal everyday to uncover a new fraud or accounting error causing a company to restate earnings or in some cases even worse. It is becoming devastating to market returns. I want to know what you think the role CPA's should play in the capital markets? And if what we are currently doing in ineffective? Furthermore should CPA's go beyond providing reasonable assurance to potential investors? And should the individual be held responsible for submitting an incorrect opinion?