Federal prosecutors in Manhattan say Deborah Duffy participated in a scheme to defraud investors in Greenwich-based WG Trading Co. from 1996 through February. They say she and others at the company failed to invest $131 million as promised and instead used it for their personal benefit.

The government says the company's customers included charitable and university foundations, pension and retirement plans and other institutions.

Two investment advisers who ran the business have been charged in the case.

Duffy entered her plea Tuesday. She signed a cooperation agreement with the government. Sentencing is set for Jan. 21.