The tape at the centre of the row, recorded in summer 2000, has the head of the Ukrainian arms exports agency, Valery Malev, proposing to ship four Kolchuga radar systems to a Jordanian intermediary in falsely labelled crates, and to send installation experts to Iraq on false passports.

BBC: Analysis: From West's favourite to pariah

But experts in the field of false confessions and wrongful convictions will tell you it happens more often than you might think.

WSJ: Officials question 2004 Buffalo murder conviction

While breast care experts acknowledge that mammography is imprecise and can lead to false positives, undue anxiety and overtreatment, they say it is the best tool they have for detecting breast cancer and that the benefits far outweigh any potential harms.

CNN: After the mammogram storm, what should women do?

But other shareholders will have to show not just that they knew Enron's statements to investors were false, but that the firms did something publicly to mislead them, legal experts say.

FORBES: Enron Probe Widens On Two Fronts

It took longer than some legal experts had expected, but Roger Clemens is finally facing an indictment over false statements to congress in February 2008, during a hearing on his alleged use of performance enhancing drugs.

FORBES: How Roger Clemens Could Have Avoided This Mess