The concern is not that the referees are prepared to use sanctions in order to restrain such dangerous play. The problem arises because the sanctions at their disposal threaten not only the offending players, but also their teams as a whole, and ultimately, the viability and meaningfulness of the match itself.
There is a further problem. There are circumstances, quite frequently, where the requirements of the game itself make it almost inevitable that a player will transgress. Where an opposing player is coming (and falling) forward at knee height in the attempt to score a try, the defender is necessarily in a quandary.
If he uses his arms to halt the ball-carrier, he is almost certain to engage that player in the head or neck area. If, in recognition of the rule against head-high tackling, he desists from using his arms, he will be guilty of a "no-arms" tackle.
In either event, he will be penalised. And this is where it gets really difficult.
The referee will not only penalise the offender and award a penalty kick but, in order to signify the seriousness of the offence, will reach for his pocket and issue a card - a yellow one, requiring the player to leave the field for 10 minutes, or a red one, that banishes the player for the rest of the match.
The referee might compound the damage by also awarding a penalty try if he believes that a try would, but for the offence, have been scored. And, in terms of piling penalty on penalty, it does not end there; the offender will then be cited after the match and will often be suspended for a significant number of weeks or matches.
And all of this for a player and a team who were doing no more than making a tackle to defend their line. There need have been no malice or ill-intention - the mere fact of physical contact is enough to constitute the offence; it is usually the posture of the ball-carrier that makes a breach of the rules unavoidable.
The referees clearly believe that they are acting under instructions when they impose this range of sanctions. The fact that most games are ruined as contests once a card has been issued seems to be of no consequence.
There is a further puzzle. It is almost as though World Rugby and the referees have come to see an ordinary penalty as ineffectual and having no teeth. But this is a mistake - the award of a penalty kick can have a great bearing on a game.
To concede a penalty can interrupt a period of dominance and good play by the team penalised. It can offer the team awarded the penalty the chance of a kick at goal or, at the very least, of biting off a good chunk of easily won territory, perhaps opening up the possibility of a line-out throw-in and drive, five metres from the opposing line.
We do not need, in other words, the whole superstructure of cards and penalty tries in order to enforce the rules - especially when there is no malevolent intention. The ordinary penalty is in most cases sanction enough. The deliberate or reckless causing of injury is of course a different matter.
Bryan Gould is an ex-British MP and Waikato University vice-chancellor.
