Five men deny conspiring to extort money for the return of the Da Vinci
A solicitor accused of helping to hold a stolen Da Vinci artwork has denied there was a conspiracy involved.
David Boyce, 63, told the High Court in Edinburgh he thought the transaction to return the painting was "unusual", but it was not suspicious.
He is one of five men who deny conspiring to extort £4.25m for the return of the painting in October 2007.
In the final evidence heard by the jury, Mr Boyce said: "I find myself embarrassed to be in this position."
The Madonna of the Yarnwinder was stolen from Drumlanrig Castle in Dumfriesshire in 2003.
Mr Boyce, who resigned from HBJ Gateley Wareing in Glasgow following his arrest, said he felt his law firm had been used to give "a cloak of respectability" to dealings aimed at securing the valuable painting's return.
He said had been approached by Lancashire-based solicitor Marshall Ronald, a lawyer he knew from earlier property dealings, who was acting on behalf of two Merseyside private eyes who claimed they could get their hands on the painting.
At the request of Mr Ronald, the business of returning the painting had been kept highly confidential, but not secret, he said.
Mr Boyce told advocate depute Simon Di Rollo, prosecuting: "I have never had any involvement in any criminal transaction in my life.
"This was something that required to be done lawfully and was done lawfully."
He agreed the transaction had been "unusual" and unique in his law career, but denied it was suspicious.
"I thought the return of a stolen painting in these particular circumstances was something laudable, if it could be done lawfully," he added.
He claimed he had not seen an agreement which contained a clause demanding that "law enforcement agencies" should not be told what was happening.
Mr Boyce said he had passed matters on to junior partner Calum Jones, another of the men on trial, and had "no reason" to look at any of the documents.
The painting was stolen in southern Scotland in 2003
He told the court: "If there was for a moment any doubt about the legality of this, I and my firm would not have been involved.
"Let me assure you of that. There was no conspiracy, no intention to extort."
On trial along with Mr Boyce are Mr Jones, 45, from Renfrewshire, and Marshall Ronald, 53, Robert Graham, 57 and John Doyle, 61, all from Lancashire.
They are not accused of stealing the painting and deny conspiring to extort £4.25m or attempting to extort the money.
Closing speeches in the trial, which is in its seventh week, are expected to begin on Tuesday.