Da Vinci accused Marshall Ronald sues Duke of Buccleuch and police chief

Marshall Ronald was one of five men cleared of conspiring to extort £4.25m

One of the men cleared of conspiring to extort £4.25m for the return of a Leonardo da Vinci painting is suing the police and the Duke of Buccleuch.

The case against Marshall Ronald was found not proven in April 2010.

He was one of five men cleared of plotting to extort money for the return of the Madonna of the Yarnwinder, stolen from Drumlanrig Castle in 2003.

Mr Ronald is suing the Duke of Buccleuch and the chief constable of Dumfries and Galloway for £4.25m.

The valuable artwork was stolen from the duke's castle north of Dumfries in August 2003.

A covert operation eventually led to its recovery following a meeting at the offices of a law firm in Glasgow in October 2007.

Mr Ronald and others who had attended were detained.

He has now resorted to the civil courts to pursue a compensation claim.

In it he claims that under the terms of an alleged contract between him and an undercover officer, known as John Craig, it was agreed he would arrange for the return of the painting in return for sums totalling £4.25m being paid.

He maintains that some of the money was being paid to people who could assist in the recovery of the painting and that it included a sum of £2m being transferred to a Swiss bank account in the name of Mr Ronald.

The duke and Mr Shearer are both defending the action at the Court of Session in Edinburgh.

The duke denies entering into such a contract and maintains any alleged contract would be unenforceable as being illegal and contrary to public policy.

During a hearing, senior counsel for the Duke of Buccleuch described it as "a hopelessly irrelevant case" and the QC acting for the senior police officer said the summons was "plainly irrelevant and quite frankly nonsense".

The artwork was stolen from the Duke of Buccleuch's Drumlanrig Castle in August 2003

Alan Cowan, for Mr Ronald, told the court that a legal aid application had been made but a decision was not expected until March and sought to have a stay put on proceedings until then.

The solicitor advocate told Lord Doherty that it was Mr Ronald's position that the case was not, as the defenders' suggested, entirely without merit.

Maria Maguire QC, for the chief constable, told the court that she considered it "highly unlikely" that legal aid would be granted.

Ms Maguire said: "It is patently obvious that John Craig was an undercover officer who was acting at all times within that role."

She added: "It cannot be possibly held with any degree of credibility that he was at any time acting as an agent of the Duke of Buccleuch or that he was entering an agreement on behalf of the chief constable of Dumfries and Galloway with this individual."

Andrew Young QC, for the Duke of Buccleuch, called it "a rather bizarre attempt" to fix a contract on the duke for something an undercover officer did in the execution of his normal investigatory role.

He opposed the move to sist - or pause - the action and said it was sought to take it as quickly as possible to a hearing to argue the relevancy of the case.

The court heard that Mr Ronald, 56, of Skelmersdale, in Lancashire, was struck off as a solicitor in England after his trial.

A discipline tribunal said he had allowed himself to become involved in "a dubious transaction" and had withdrawn money from a client account without authority.

Lord Doherty said he was not prepared to exercise his discretion to put a stay on the action and awarded expenses against Mr Ronald.