The government is considering letting retailers and pubs conduct their own test-purchasing operations to stop underage sales of alcohol if they can show consistently strong pass rates, The Grocer has learned.

"A leading off-trade retailer was advised by the Home Office that if it continued to maintain its high pass rates it would be left alone," said an insider.

Independent test purchasing company Serve Legal said a move to self-regulation, similar to one that operates in other ­age-restricted industries, was overdue. "We have seen pass rates in both the grocery and pub trades rise steadily during the past three years, with a consistent performance of 80% and higher for many companies," said director Charlie Mowat. "Now it is time to echo David Cameron's vision of a big society; for people, companies and the retail industry as a whole to take more responsibility."

Serve Legal has carried out independent test purchasing of age-restricted products via 100,000 site visits in the past four years across supermarkets, ­c-stores and pubs.

Its research also shows that pass rates in other ­age-restricted industries, such as gambling and knives, which already self-regulate, had risen at a much faster rate than they have in the licensed trade. "Operators responded positively to the challenge of taking on more individual responsibility with better recruitment, more regular training of staff and regular independent testing of ­procedures," said Mowat.

With pass rates gradually rising and set to go up again this year, self-regulation for those that have proved themselves ­responsible would not just benefit retailers, he argued. Local authorities would be able to invest in education programmes about the dangers of drinking too young and too much.

Another industry expert said that the government may be looking to cut back on test-purchase operations as part of its public spending cuts and thus getting the industry to ­cover any shortfall.