The former accountant of convicted con artist Bernard Madoff has pleaded guilty to several charges, including fraud, in connection with his auditing work for Madoff.

David Friehling, 49, had to appear in a Manhattan federal court on Tuesday. He is the third person to plead guilty in the multi-billion dollar fraud.

The accountant, who served as Madoff's outside auditor since 1991, confessed to US District Judge Alvin Hellerstein that he didn't conduct an independent investigation of Bernard L. Madoff Investment Securities LLC as accounting rules required of him.

“In surely the biggest mistake of my life, I placed my trust in Bernard Madoff,” Friehling told Hellerstein. “I am truly sorry for the suffering of all the victims.”

Madoff is serving 150 years in prison and his aide Frank DiPascali is in jail awaiting sentencing.

Friehling, a resident of New City, a northern suburb of New York City, faces 114 years in prison and is seeking leniency by cooperating with the government. He was freed on $2.5 million bond after entering his guilty plea.

Friehling is a past president of the Rockland County chapter of the New York State Society of Certified Public Accountants.

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