Important legal note : since this article was published, Mark Duncan was found 'not guilty' on all charges brought against him.

TWO crooked antique dealers tricked frail and vulnerable aristocrats out of valuable heirlooms for a fraction of their value, a court was told yesterday.

Mark Duncan, 33, and Lee Collins, 39, allegedly targeted the Earl of Lauderdale, a descendant of Lord Baden- Powell, the founder of the Scout movement, and the widow of the artist Charles McCall, among others.

The pair, known as “knocker boys”, cold-called their victims and pressured them into letting them stroll round their homes to look at valuable paintings, jewellery and furniture, the jury at Blackfriars Crown Court, London, was told.

Brian O’Neill, for the prosecution, said that the men would then offer the owners a fraction of the items’ value, convince them they needed repairing, or simply pocket them and walk off. The valuables were sold at auction houses around the country for a large profit.

It was claimed that the pair made £680,000, much of which was laundered through the accounts of families and friends.

Mr O’Neill told the court that the conmen set up their fraud by posing as directors of the fictitious Sheraton House Antiques, based at an accommodation address in Mayfair. “It was one that was deliberately chosen to convey the impression of respectability and legitimacy and to open doors which might otherwise be closed to them as a consequence,” he said.

“Using this pretence they were able to inveigle their way into the homes of many rich, elderly and vulnerable men and women whom they proceeded to con and steal from.”

He said that many of the victims felt threatened and intimidated into agreeing to hand over their antiques, and others were unaware they had been defrauded.

At least 13 people are alleged to have been targeted by Mr Duncan and Mr Collins between February 2003 and April 2005.

Mr O’Neill said that Mr Collins conned Dorothy Baden-Powell out of a pendant, forcing her to accept £150.

Mitzi McCall, 87, the frail and confused widow of the artist Charles McCall, had sold her husband’s treasured drawings to the pair for £10,000 after a visit from Mr Collins in November 2003.

The Earl of Lauderdale, then 93 and suffering from dementia, had been tricked into selling an armorial urn worth up to £600 for £100.

Mr Collins and Mr Duncan were also said to have deceived Lady Grenside, an elderly widow, into selling books and jewellery, and convinced another pensioner who had since died to part with a painting and family silver.

Mr O’Neill said that the men’s modus operandi included mail shots or cold-calling people they thought might own valuables. “Should the target express an interest in their services, the defendants would visit their home, often unannounced, in the hope of finding something of interest,” he said.

“Once inside they would walk round the property as if it were their own, opening cupboards and drawers, removing paintings from walls and sifting through valuables.”

If something caught their eye a variety of techniques would be employed. “One was to cajole, harangue and deceive the owner into parting with the item for a fraction of what it was worth.

“Another was to convince the owner the item was in need of repair, for example riddled with woodworm or damaged in some other way. They would then offer to undertake the necessary work and return it.”

Mr O’Neill said that Mr Collins would occasionally “appropriate that which took his fancy and simply steal the item without regard for the owner’s feelings or rights”.

Mr Duncan, of Buxted, East Sussex, denies conspiracy to defraud, conspiracy to launder money and eight charges of obtaining property by deception.

Mr Collins, from Brighton, denies conspiracy to defraud, conspiracy to launder money, 11 charges of obtaining property by deception and 3 of theft. The trial continues.

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