As if the American International Group (AIG) case was not complicated enough, a deal cut with Joseph H. Umansky may further complicate cases being brought forth by the Justice Department and the Securities and Exchange Commission, the New York Times reports.

Spitzer has already cut a deal with Umansky, sacrificing the former AIG senior vice president for the bigger fish of former chief executive Maurice R. "Hank" Greenberg. The problem comes when federal authorities go after AIG itself, Greenberg, and former chief financial officer Howard I. Smith, since the evidence must not come from Umansky's immunized testimony. In an unusual move, Spitzer has referred to this testimony in his own complaint.

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