Tagged Bret Ravenhill spent three months fighting the urge to break his curfew " after the tracking device was fitted to his false leg.
Bret, 29 " convicted of possessing cannabis " was amazed when a Group 4 security worker failed to spot his left leg was made of metal and detachable.
The forklift driver grinned yesterday: “Two friends were at my house when she came round and were killing themselves laughing.
“I thought she would realise straight away " but she never bothered to turn up my trouser leg or look underneath my sock.
“I just left things as they were for a joke.”
Bret, who was given probation by a judge and barred for three months from going out at night, had his tag checked every four weeks and still no one realised.
In between he would prop his artificial leg in a corner and wear a spare in Barnsley, South Yorks.
Bret, who lost his limb in a motorbike crash six years ago, said: “I didn’t break my curfew once " but I could have been out living it up every night. I’m no danger to the public " but what if they’d done the same thing to an armed robber?”
Even when the tag was finally removed this week no one was the wiser. Furious Justice Minister David Hanson, said: “I am very concerned.”
As Group 4 launched a probe, a spokeswoman said: “We conduct our monitoring operation under rigorous procedures which include carrying out an assessment of the leg that is being tagged.
“It would appear that in this instance the procedure has not been followed.”