Writing in the FT this week, John Kay tackles the claims made by the health lobby for the impact of the ban on smoking in public places and the potential benefit of reducing the limit on blood alcohol for drivers.

In both cases, he shows that the statistics quoted by proponents are tortured “to reveal conclusions that do not obviously follow from them”.

“It is time to reassert the principle that research must pursue the truth wherever it leads,” he writes. While the objectives being pursued may be worthwhile, this principle should not be sacrificed.

The problem that local retailers face in resisting the display ban is that the stories are already out there and mostly unchallenged. So many MPs believe that the smoking ban is a good thing and a popular piece of legislation that they are open minded about adding further legislation on top.

While Mr Kay’s comments are useful, local retailers cannot turn the clock backwards. However, they do need to challenge the validity of any statistics used by pressure groups to impose further regulation on their businesses. The clever presentation of numbers can often mislead. Be on your guard.