Donald Findlay has revealed successfully defending Paul Ferris for murder was his top courtroom moment.The QC represented Ferris when he was accused of killing Arthur Thompson junior in 1992.He was sensationally acquitted of the death and, at the time, it was the longest and most expensive criminal trial in Scottish legal history, costing £4 million and lasting 54 days.Ferris was a teenager when he was recruited as an enforcer for Glasgow's biggest crime clan boss, Arthur Thompson.He had been