Michael "The Ambassador" Underwood appeared on the doorsteps of wealthy widows in Crowbourgh, London and the Isle of Man to persuade them to part with treasured possessions, it is claimed.
His solicitor, Anthony Hershal Blok, is accused of hiding a £300 receipt for a painting Underwood bought worth £30,000 or more on the open market.
Underwood, of Copenhagen Court, Brighton Marina, went to prison in 2006 rather than reveal the fate of the work, entitled "Girls On A Beach" by Sir William Orpen, Brighton Crown Court was told.
He is accused of failing to declare ownership of the work when he filed for bankruptcy in 2002 so it would not be seized to pay his debts.
The court was told that Underwood had been a client of Blok since 1995.
The prosecution claims Blok had files containing the cash proceeds of crime by other clients in his office.
Blok is accused of lying to a court by claiming he did not know the identity of the Orphen painting's owner.
Blok is also accused of failing to pass on information about suspected money laundering by people he represented as a criminal lawyer.
Amanda Pinto QC, prosecuting, said Underwood had tried, since obtaining the painting in 1993, to get it removed from a register of missing and stolen artwork so he could sell it.
She said, "They made concerted efforts to legitimise the painting, which had been obtained in criminal circumstances by Mr Underwood."
Blok, 71, of Gowan Avenue, Fulham, faces charges including two counts of perjury, three counts of failing to disclose evidence of money-laundering, and one count each of transferring criminal property, assisting another to obtain property which was a proceed of crime, and possession of criminal property.
Underwood, 64, of Copenhagen Court, Brighton Marina, is accused of concealing criminal property and perjury.
Underwood has a previous conviction for dishonestly obtaining property from an elderly woman in Chelsea. In that case, retired Sussex Police Art and Antiques Squad Detective Simon Muggleton, of Corsica Road Seaford, traced a stolen Porcelain plaque back to 1948, thereby showing Underwood and his accomplice Lee O'Donell were guilty of deception, for which Underwood was jailed.
Both men deny all charges. The trial is expected to last five weeks.
Art Hostage comments:
This is a case of sweet revenge for ex-Sussex Police Art and Antiques Squad icon Simon Muggleton, who has had a long personal feud with Michael "The Ambassador" Underwood.