Two calls in a row prompted me to revisit the subject of alcohol test purchasing. Pawan Joshi, who runs a Spar store in a village in Derbyshire, got a letter telling him that the store had failed a test purchase. It was the second time.

"I rang and asked what had happened because I want to correct it," he told me. "What procedure did they follow? But they seem to have a holier-than-thou attitude. I don't know how to reprimand staff and it's difficult to fire people these days."

Pawan is worried about the 'three times and you're out' policy now being followed (some would say pursued) by local authorities.

My next caller, Kevin Jones, who runs a Premier store in Flintshire, North Wales, tells me that he recently attended a seminar set up by his local authority to address the issue of selling to the underaged.

"It was quite obvious that they are on a mission," he observed following a police presentation. "I asked them how many youths they had caught attempting to purchase and some were quite surprised by my angle of attack. They expect us to be the police, but we are often having to deal with druggies and robbers who may even be carrying weapons.

"With Trading Standards' 'stings' they tell you when you're wrong, but not when you're right. They should be made to tell us when we are right so that it can be weighed up against any mistakes. Staff who get fined may have got it right 20 times before."

He sums it up: "The question that needs to be asked is why are the police not aware that it's against the law to attempt to purchase?"

Any time when a youngster has alcohol there are, he adds, four possibilities. The kids may have stolen the stuff; someone else may have purchased it for them; they might have got it from their parents; or they may have been sold it.

"Why are the police ignoring the other possibilities?"

Kevin has a gruesome case, too. "We had someone proxy purchase. It turned out to be the kid's uncle. The nephew had to have his stomach pumped and the uncle got fined £80."