Is it about to become illegal for parents to discipline their child with a smack? We might have known that the already top-heavy Children’s Wellbeing and Schools Bill would be hijacked by those with an agenda to push. Lowestoft MP Jess Asato has tabled an amendment, backed by 26 MPs (including surprisingly one Tory), that would abolish the legal defence of reasonable chastisement. This would criminalise all physical punishment even within the home, as has been done in Wales and Scotland. A number of organisations have already lined up behind her, including Humanists UK and the Royal College of Paediatrics and Child Health (RCPCH). This amendment must be resisted.

The movement for a smacking ban is overwhelmingly comfortably middle-class

There are clear arguments of principle and policy against the ban on smacking, which would involve a massive intrusion by the state into family life. It would deprive overworked parents of what is often an effective way of keeping order. It would also encourage childish disrespect for adult authority, give children an unholy hold over adults who once forgot themselves (‘Do this or I’ll tell the police what happened last Tuesday’) and further encumber our already grotesquely overloaded social services.

Nor are the reasons in favour of the ban very convincing. The suggestion that even a reasonable tap on the bottom risks ‘really significant physical harm’ is, to say the least, thin; the fact that there are some children who don’t respond to a light smack leaves out those that do. That other countries have banned smacking is beside the point; rather more have not. That UN functionaries and the human rights establishment have for years demanded a ban might even suggest to some that there is something right about the present law. And there is something seriously desperate about the argument from the RCPCH child protection officer that the amendment is ‘not a new law, it’s just removal of a technical defence’. As an exercise in disingenuity, this takes some beating (so to speak).

But the objections go deeper. It is unacceptable that momentous changes to our law should be insinuated by way of amending Bills on rather different matters. (We saw a glaring instance last year, when Labour MP Stella Creasey sought to upend our abortion law on the coat tails of an amendment to the Criminal Justice Bill, an attempt thankfully frustrated by the election.)

The reason for this objection is obvious: major changes in social policy need extensive discussion and mature thought, both in and out of parliament. This is precisely what they will not get if they are introduced by adventitious amendment to a larger Bill. This carries a distinct danger that changes could slip through without much opposition because a House with many bigger fish to fry has limited time to discuss them, and its members rather want to get home.

One suspects, indeed, that this is precisely what Jess Asato and those behind her are hoping for. There is a great deal of meat already in the Children’s Wellbeing Bill – heavy restrictions on home schooling, curtailing the independence of academies, and so on – which is likely to create a great deal of discussion. By leaving little opportunity to probe her proposals, this might give her a chance to get them through almost on the nod.

The movement for a smacking ban is overwhelmingly comfortably middle-class: politicians, academics and the liberal establishment. These mostly neither understand nor sympathise much with the outlook of those at the sharp end of child-rearing.

Yet ask a busy White Van Man in the suburbs, a frazzled immigrant parent in an urban high-rise, or a just-about-managing mother in a poky house in a Red Wall seat, and you are unlikely to hear much enthusiasm for the idea of turning even a light slap to a child into a police matter and empowering stroppy seven-year-olds to make life difficult for their parents at bed time. You are much more likely to see a strong feeling that how parents discipline their children should be up to them. They will also be conscious of a youth that seems to be running wild and the need to curb it by any means possible.

These people would be difficult to convince about the virtues of a ban, and as constituents would undoubtedly ask some very awkward questions. Add to this what would probably be a hostile popular press and a government sceptical about devoting parliamentary time to a potentially unpopular measure, and the difficulties of putting forward a smacking ban in a separate Bill subject to extended discussion become clear.

If the best chance for Jess Asato is to curtail discussion as much as possible, this should give a hint to those who wish to defeat her. They need to make the loudest noise possible about what is wrong with this amendment, to their MP and anyone else who will listen. They have nothing to lose; family life has a great deal to gain.