All hell broke loose. The chattering classes of north London, where the Blairs then resided, chattered that the editor and his deputy were chauvinist and ignorant. Had we not heard of the cab rank principle, whereby barristers are obliged to take whatever case is next in the queue? Did we not understand how insulting it was to suggest that a woman’s professional life had anything to do with her husband?

I suppose that press respect for these principles explains why Ms Booth’s recent advocacy before the House of Lords on behalf of a 17-year-old expelled from school (staff refused to teach him when he was reinstated by the appeals panel) has occasioned little comment.

Newspapers will be unfair to teachers, social workers, train drivers or firefighters but they will rarely be unfair to lawyers, doctors, bankers or police officers. I do not blame them. I have no intention myself of flouting the conventions again. In any event, if Ms Booth were to bother about government policy on exclusions, she would have difficulty establishing what it is - it could have changed again during the hearing.

I am not surprised such cases have ended in the courts, or that ministers struggle to find the right policy. Discipline is now the most contentious area of schooling. Nothing angers teachers more than society’s apparent failure to back them against unruly and even dangerous pupils; nothing angers parents more than a school’s use of arbitrary power over their children.

I sympathise with both. Teachers’ pay and job prospects increasingly depend on exam and test results, and a school’s future may be jeopardised if it comes low down the league tables. It takes only a couple of pupils to disrupt the learning of an entire class, and probably shred the teachers’

nerves as well. You cannot blame heads and teachers who are determined to get rid of troublemakers.

Equally, school qualifications now determine not just job prospects and income but also, if we believe the research, mental and physical health. Expulsion, therefore, becomes a draconian penalty which requires due process, including a right of appeal.

But street-wise heads have a quiet word with the parents. “Your child is not settling down here. It might be better if he made a fresh start elsewhere. It would be most unfortunate if he had an exclusion on his record.”

The aim is to avoid legal procedures. In the same way, smart employers avoid sacking people they want to get rid of and minimise the risk of an industrial tribunal.

Strong schools can afford to do this. Weak schools, terrified of falling rolls and falling funds, cannot - they often provide the “fresh start” for the child eased out of the school down the road. Overloaded with disruptive pupils, they slip further down the league tables.

Those heads who are reported to have “turned round” such schools have nearly always expelled or eased out a handful of troublemakers. Though nobody ever admits it, this is far more important than easing out supposed “dead wood” among the staff.

Employees who think they have been unfairly eased out of jobs can sue for constructive dismissal. I wonder if we shall soon have pupils bringing cases for constructive expulsion.

Peter Wilby is editor of the New Statesman