Measuring the impact of a light smack

The effects of smacking as a form of parental discipline have been debated for many years. Despite hundreds of academic papers on the effects of smacking, it still isn’t clear what the effects are.

There are many reasons. How do you even begin to measure the impact lightly smacking a young child has on them when they grow up? Is it even possible?

Those demanding a smacking ban often claim the case against parental smacking is supported by science. But as we’ll see, there are many problems with that claim – not least since scientists don’t agree on what counts as smacking.


The definition of smacking can vary greatly between studies. Some call it a light tap on the hand, and others don’t even define the term. Various studies on smacking even conflate mild, reasonable parenting with unduly cruel or abusive punishment. As a result, the data being analysed may include parents hitting their children in physically abusive ways which are already illegal.

This variation in definition makes it difficult to compare results between studies. Where research has combined light discipline within a loving family with harsher corporal punishment such as punching or hitting, the effects of light smacking on children’s development will be impossible to tell.

A big problem with smacking studies is the difficulty in measuring the severity of the punishment. Unreasonably heavy smacking unquestionably should be (and already is) illegal. But a blanket injunction on all smacking, however light and loving, will not further prevent abuse. Those who abuse their children will do so whether there is a smacking ban or not. What we need is better enforcement of the current law, rather than it being widened.


Part of how studies define and categorise smacking relates to the frequency of the punishment. This presents another limitation of the science. This point was acknowledged in a recent review of smacking studies. It noted that “the magnitude of the effect varied with the frequency of the punishment”. So it remains unproven that infrequent mild smacking is a driving force behind poorer childhood outcomes.

Mild, infrequent smacking is often ignored and counted as ‘never smacked’, or set alongside much more frequent and harsh action by parents. Loving parents who do choose to smack are therefore often counted by the studies as having never smacked their children. Yet the results of studies are misused to argue for a ban on even the most infrequent smacking.


Studies often deal with very minor correlations between smacking and several negative outcomes. Though these may be ‘statistically significant’ and receive academic attention, there is well warranted disagreement over whether they have any practical significance in the real world.

The research is also presented as if the average correlation between physical punishment and a particular outcome applies equally to all children in all situations. But of course children do not experience the effects of smacking equally – the impact can be ‘moderated’ by the meaning children attach to it, the level of warmth in the parent-child relationship and even the child’s temperament. We cannot assume uniform effects from scientific trends. This is an inbuilt limitation in scientific studies.

Methods of discipline can be discussed and debated, but to criminalise parents for a loving smack goes beyond the remit of scientific studies.