As federal investigators probe the woes of insurance giant American International Group, the name of one former executive keeps surfacing in connection with the firm's failure and the need for a multi-billion-dollar emergency government loan package: Joseph J. Cassano.

Cassano, 53, ran the company's London-based financial products unit, which trafficked in relatively risky credit-default swaps. During congressional testimony last week, Rep. Jackie Speier (D-Calif.) called him "the golden boy of the casino in London." The New York Times has noted that Cassano's "freewheeling little 377-person unit ...flourished in a climate of opulent pay, lax oversight and blind faith in financial risk models."

But as the mortgage derivative market started to unravel, Cassano's division began racking up losses -- $11 billion by last February.

During his eight years at AIG, Cassano earned $280 million and, after leaving the company in March, was slated to receive $1 million a month (document) as a consultant through the end of 2008, disclosed Rep. Henry A. Waxman (D-Calif.), the chairman of the House Oversight and Government Reform Committee.

Cassano's contract was terminated the day before a congressional hearing on AIG's collapse last week. (Waxman called the government's $123 billion bailout of AIG a "direct result" of the losses incurred by Cassano's department.)

Cassano's lawyer, F. Joseph Warin, defended his client's reputation to the Wall Street Journal, saying that determining values for the swaps in a rapidly changing market is complex and that "it can't be the case that your [trading partner in swaps transactions] is the definer of what the value is." He said that Cassano has been cooperating with investigators.

Joseph J. Cassano, AIG's former financial products division chief, was named one of the "10 Most Wanted Culprits of the Collapse" by CNN.

At the Hill hearing, it was revealed that PricewaterhouseCoopers, the company's auditor, complained of a lack of access to Cassano and his London-based unit.

Likewise, a former AIG auditor, Joseph W. St. Denis, wrote in a letter to the congressional committee that he found out in September 2007 that Cassano's unit had been asked for billions of dollars in collateral related to derivatives it had sold, The Wall Street Journal reported.

"I was gravely concerned about this," St. Denis wrote in the letter (PDF).

St. Denis wrote he wasn't personally involved in the valuation of the swaps at the unit. In the last week of September 2007, St. Denis wrote that Cassano said he had "deliberately excluded" St. Denis "because I was concerned that you would pollute the process."

St. Denis said he thought "pollution" referred to the "transparency" he proposed to the firm's accounting policies. He later resigned in protest.