Richard Owens’s eyes follow my scribbled notes as he talks. He is a former assistant US attorney in the Department of Justice (DoJ), most recently head of the securities fraud unit in Manhattan, and his gaze is penetrating. Name a famous American white-collar criminal case and Mr Owens and his team were probably probing and prosecuting. Think Bernie Ebbers, Frank Quattrone and Martha Stewart.

My scribbles become more chaotic and messy and his stare becomes more intense. Are my notes accurate? What if Mr Owens subpoenas the notebook as evidence? Will I have to read my scribbles in court?

He and Sean Berkowitz, also a former assistant US attorney and a lead prosecutor in the Enron trial, have quit game-keeping for the more lucrative world of poaching in Latham & Watkins, a big American corporate law firm.

Are they in London to tell British businessmen to beware the long arm of the DoJ? “It’s probably less of a threat, now that we are not there,” Mr Owens says.

These guys are quick on their feet, but look slightly uncomfortable in the swish but sterile corporate environment of Latham & Watkins’s City offices. You want to see them in a drab government office with venetian blinds, strip lighting and stale coffee in plastic cups.

Mr Owens is dry, Mr Berkowitz the more ebullient. The latter became famous for his theatrical presentation at the summation of the Enron trial last year, when he held up a placard to the jury with the words “Truth” and “Lies” boldly displayed in black and white. “You get to decide what’s right,” he told the jurors. “You get to decide whether they told the truth or whether they told lies. Black and white.”

They decided: lies. Jeffrey Skilling, Enron’s president, was convicted on 19 counts of conspiracy, fraud and insider trading. Kenneth Lay, the chairman, was convicted of six conspiracy and fraud counts.

The defence spent $100 million on the case but, according to Mr Berkowitz, the prosecution’s strategy was not to get embroiled in the nightmarish complexity of Enron’s business in an attempt to criminalise aggressive business practices. “We tried to avoid that,” he says. “Virtually all of those complicated transactions were approved by outside lawyers.” Instead, the strategy was to get them on “simple lies”.

Those little fibs that you told your accountant will hang you in the end. The fraud cases that end up in a media scrum outside a court can start in various ways, Mr Owens says. It can be a company that runs out of cash, as with Enron, or a whistleblower, as happened with both Enron and WorldCom.

More often than not, it starts with a newspaper article. Every morning, Mr Owens says, he scrutinised the financial pages looking for people to subpoena. It was a banal report in The Wall Street Journal about a sale of stock in ImClone Systems, a pharmaceutical company, just days before the US Food and Drug Administration declined to approve a drug that led to Martha Stewart, the television personality, serving a five-month jail term for obstruction of justice. Mr Owens says: “I circled the article with a red pen, walked down the hall with The Wall Street Journal under my arm, found a prosecutor and said: ‘This stinks, cut some subpoenas.’ Next thing we knew, Martha Stewart was in our office, lying.”

Telling your lies in Europe won’t necessarily help you, according to the two former prosecutors, who point to an increasingly aggressive assertion of jurisdiction by the DoJ. Three British bankers are awaiting trial in Texas on Enron-related allegations, while Ian Norris, the former chairman of Morgan Crucible, is appealing to the House of Lords against extradition to the United States in a price-fixing case. If you work for an American company, or if your company has issued stock in the US or is listed in the US or takes part in a cartel that affects the US, the DoJ reckons that you are in its bailiwick and are fair game.

“The US is looking to enforce the full extent of its jurisdiction,” Mr Berkowitz says.

That includes the Foreign Corrupt Practices Act, which was used against Statoil, the Norwegian oil company, which was accused of bribing Iranian officials. In the first half of last year, 50 prosecutions were launched in America under the Act. That compares with nil prosecutions in the UK and one notable retreat – the British Government’s decision not to pursue BAE Systems’s alleged bribery of Saudi officials.

Mr Owens believes that this could change. “If I were to predict a trend, the increasing aggression of US prosecutors will prompt Europeans to pursue a similar strategy,” he says. “If you are a regulator, the last thing you want is for the public to think you are asleep at the wheel. That could result in a competitive race [to prosecute], which would be very bad for businesses.”

The US is pursuing white-collar crime with zeal. It is politically popular and makes good television. For Mr Owens, occasionally it meant curbing the enthusiasm of his own staff in high-profile cases. “It was a real challenge to keep the egos of my subordinates in check,” he says. He did it by keeping his own media appearances to a minimum and by “reminding them of who they really are”.

Many more fraud cases may be on the horizon, the two men reckon, as the economic cycle turns. In the 1990s boom, it was stock market manipulation, often involving traditional crooks and “the Mob”. Then it was Enron and WorldCom as the dot-com bubble burst. A new downturn will lead to a new flight of capital, accounting scandals and fraud as desperate people try to keep their finances afloat. Mr Berkowitz reckons that the debacle in the sub-prime mortgage market is already fruitful territory.

White-collar crime is rarely about greed, in the opinion of the former prosecutors. “It is generally hubris,” Mr Owens says. “It’s a corporate culture that is detached and guarded by advisers who never challenge.”

The partners

Sean Berkowitz a litigation partner in Latham & Watkins, Chicago, graduated from Harvard Law School and was previously director of the Enron task force for the US Department of Justice. He served as lead prosecutor in the case against Kenneth Lay and Jeffrey Skilling

Richard Owens a partner in Latham & Watkins, New York, is a graduate of Harvard Law School. He served 12 years as assistant US attorney in New York’s Southern District and was chief of the securities and commodities fraud task force between 2002 and 2006. He supervised prosecutions relating to WorldCom, Adelphia Communications, Martha Stewart and Royal Ahold

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