A North Shore man who for years helped manage the assets of a prominent and wealthy Massachusetts family has pleaded guilty to bilking the family office of some $20 million, according to the Boston Business Journal.

John Doorly had previously denied any wrongdoing in the matter involving the descendants of industrialist Frederick Ayer. But Mr Doorly later pleaded guilty to mail fraud and money laundering.

A prosecutor told a US District Court that from 1999 through 2006, Mr Doorly "removed millions of dollars from the bank accounts of Tenens Corporation, and used the money for his own purposes," US Attorney Carmen Ortiz's office said in a prepared statement released late yesterday, the publication said.

The statement detailed those purposes as "the acquisition, use and maintenance of three airplanes (total cost of more than $12.0 million); the purchase of mortgage free houses and condominiums for family members, friends, and mistresses; the purchase of golf memberships at exclusive clubs across the United States for himself and his son; transfers of hundreds of thousands of dollars to his wife and his mistresses; and the payment of hundreds of thousands of dollars of personal credit card bills.”

The publication said the man could be jailed for up to 20 years.