When Bradford magistrate John Waldron cast doubt on the benefits of electronic tags, it was suggested he try it out himself.

Mr Waldron agreed to let tagging company G4S put him on a curfew at his home for a weekend.

“It wasn’t heavy but it did take me a couple of hours to get use to it being there,” he said.

“I have to be honest, I thought staying home between 7pm and 7am would be easy but it wasn’t.

“The first evening I paced the house wondering what to do and was disappointed that I had to turn a friend down who invited me to join them for a drink.

“The second night I was late home. I was more than a little bit embarrassed that G4S knew the very second that I returned home.”

Mr Waldron admitted spending a lot of time “messing with it” to see if it would fall off and confessed on the second day to cutting it off himself.

“Within moments the monitoring unit began ringing. G4S had recorded the strap cut from their Customer Service Centre in Manchester,” he said.

G4S monitors 12,500 people in tags in the UK, of which approximately 1,000 are in the West Yorkshire area A G4S spokesman said: “Tagging is a key part of the Criminal Justice System. A number of independent studies have shown tagging provides value for money.”

Mr Waldron said: “As an individual it was strange to think G4S knew my comings and goings, but as a magistrate this was excellent proof and reassurance that the system works.”