A Carfin man caught with drugs worth £640,000 was wearing a prison officer’s uniform at the time.
Police believe Lawrence Simonini donned the outfit in a bid to look respectable as he drove north along the M6 and M74 from Liverpool, the High Court in Glasgow was told.
Russell Baillie, the warden it belonged to, claimed he gave the uniform to Simonini to wear at a fancy dress party.
However, the jury didn’t believe that story and Simonini (29), of Dalmore Crescent, and Baillie (31), of Shotts, were convicted of being concered in the supply of amphetamine.
The court heard undercover cops were tracking the pair’s movements and Simonini’s hire car was stopped in March 2014.
Baillie worked at Cornton Vale Prison in Stirling, but was off with depression when he and Simonini drove south to pick up the drugs. Baillie travelled home by train.
Baillie said: “I know nothing about any drugs. I went to Liverpool for a day trip.”
Simonini said he knew nothing about drugs and thought he was bringing a load of fake jeans to Glasgow. He claimed that he wore the prison outfit only because Baillie told him to.
A third accused, Joshua Quinn (26), from Liverpool, was found guilty of being concerned in the supply of amphteamine in August 2013, on journeys between Renfrew, Larkhall and Paisley.
All three accused were granted bail and will be sentenced next month, but judge John Morris told them: “Make no mistake you will be going to jail.”