After a decade of trying to convince US authorities that Bernard Madoff's seemingly high-flying hedge fund was a scam, the man whose warnings could have saved a lot of money for a lot of people issued a terse message to the world: Leave me alone. He will talk to Congressional investigators and that's it. Madoff stunned the world in December when he allegedly admitted to running a “giant ponzi scheme” that investigators have said cost investors $50 billion. Harry Markopolos, a 52-year-old former financial executive had been onto Madoff since 1996. Members of Congress have repeatedly invoked Markopolos name in questions to the US Securities and Exchange Commission about how it missed the $50 billion fraud. “Why in the world didn't anyone respond to his allegations?” asked Rep. Carolyn Maloney, a New York Democrat, referring to a 19-page memo Markopolos wrote to the SEC in 2005 titled, “The World's Largest Hedge Fund is a Fraud.” Markopolos said in a statement that he would work with Congress and the SEC, but then wanted to get out of the spotlight. “Once his Congressional testimony is complete and his cooperation with the SEC Inspector General's investigation concluded, he wishes to return to private life,” the former chief investment officer of Boston-based Rampart Investment Management Co said in a statement released on Friday by his attorneys. Despite having identified the fraud early Markopolos is not so proud of his unsuccessful nine-year campaign with the SEC against Madoff, according to media reports. Markopolos turned his analytical focus on Madoff in 1996 after his boss asked him to figure out how to match the returns of Bernard L. Madoff Investment Securities LLC. Years of analysis convinced Markopolos that it was impossible for Madoff to consistently outperform markets so dramatically.