Louis J. Freeh, the former director of the Federal Bureau of Investigation, was asked on Friday to become the trustee for MF Global as it seeks to unwind itself in bankruptcy court.

The choice of Mr. Freeh, 61, comes as MF Global faces inquiries by several government agencies, including the F.B.I., into its demise. Investigators are still searching for hundreds of millions of dollars in missing client funds, which by one estimate now totals $1.2 billion.