Now, due to the rather convoluted way in which licensing offences are dealt with, those details might be more difficult to extrapolate south of the border.

The introduction of PNDs — fixed penalty notices for disorder — has given the police the opportunity of “ticketing” staff who serve drunks, and so far I have not seen details of the extent to which this provision has been used. But it still raises some issues of concern.

It is a fact that one of the very first things that new entrants to the trade learn about their legal responsibilities is that you must not serve someone who is drunk. But no one ever explains what that means, because there is no legal definition: it is a “popularly-accepted term”, to use the phrase of one judge, but it covers a multitude of sins and is very difficult to determine exactly.

It does not mean “over the legal limit for driving”, even though we use the term “drunk driving” to describe it. Responsibility for ensuring that a person is fit to drive within the law rests with the individual, not the licensee. You can dissuade or deter a person from driving home, but as a leading case has shown, the licensee is not vicariously liable for what the driver does if he is over that limit, unless there are very special circumstances.

What it means is that if someone walks up to the bar and you can see that they have had too much, you must not serve them. They will “appear to be drunk” and at that stage you risk prosecution if you give them any more alcohol. You also risk a degree of aggression at the same time, because people in that state may not agree that they have had enough. But refuse them you must.

Taking you to court for it, however, may not be the best option for the police, because the word “knowingly” has been inserted in the relevant section, in front of the phrase “sells or attempts to sell”. This means the prosecution has to show that the licensee or member of staff must have known the person was drunk from their appearance or disposition, or possibly from the amount of drink that they had already served them.

The most likely scenario, of course, is the police enter premises, which are still serving, and several of the people in the bar are clearly drunk and have drinks in front of them. There may also be a degree of disorder, which might render the licensee liable to a separate prosecution.

The evidence the police might then bring forward would include the state of individuals (speech slurred, unable to stand properly, glazed eyes etc) to show that the barstaff have turned a blind eye to the condition of their customers.

But in many cases it will be a value judgment. A happy party of revellers on a Friday night, perhaps celebrating a promotion or a birthday, might not be committing disorder, but will be loud and raucous and have put away a number of drinks. There may come a point when a member of that party seeks another drink and you can see they are not in control.

That is when the law obliges you to refuse service, involving another member of staff if necessary. You do not want an on-the-spot fine or, even worse, loss or suspension of the licence, for serving one too many.