TWO men who watched a botched attempt to cut open a security van cash box have walked free after a judge wondered why they were in the dock.

Judge Lord Turnbull admitted he was puzzled about exactly what Christopher Dickson, 23, and Jamie Robertson, 24, had done wrong.

Both had been in custody since they were arrested last Hogmanay. They were originally charged with robbery but pleaded guilty to a reduced charge of reset.

The court heard how a Group 4 van delivering cash to the Bank of Scotland branch in Neilston Road, Paisley, was attacked by two youths in dark balaclavas and a security box containing £1500 was taken.

The youths sped off in a getaway car, which was later found abandoned near Auchenlodment Road, Johnstone.

Hours later police stopped another car because they thought the driver might be breaking a court curfew. Also in the car were Dickson and Robertson.

Robertson's T-shirt showed traces of purple dye - the kind used by security firms to protect their cash boxes. If the boxes are tampered with a small explosive device is detonated, spreading the dye through the bank notes.

Robertson and Dickson refused to answer questions and that, their lawyers said, was their big mistake because they had connived at preventing the cash box being returned to its rightful owner.

The High Court in Edinburgh heard the two men were together when Robertson received a phone call from another man asking to borrow a Stihl circular saw.

Robertson, with his connections in the building trade, was happy to oblige and Dickson went with him to Auchenlodment Road.

They watched as an attempt was made to open the box and ran for it when the explosive device went off.

As the lawyers told their story, Lord Turnbull interrupted to ask: "I wonder what the nature of the criminality was?"

The judge admonished both men and told them: "I have never encountered such limited culpability in my involvement with the High Court."