Last week, at Swansea Crown Court, a rugby player was jailed for 15 months for stamping on an opponent’s head. Rhys Garfield, 23, was playing for his Pontycymmer village team when he violently stomped Glynneath’s Gareth Howells. The wound needed 30 stitches.

There is a legal difference between virile play and vicious play. In 2007, it is more common for conduct in sports such as rugby, football, and even cricket, to result in prosecutions than it was in 1907. But when can a prosecutor run past the referee or umpire and pull a sportsperson before a judge?

The leading case on violence on the football pitch is R v Mark Barnes, from 2004. The principles used to decide the case can be applied to all sports.

On December 7, 2002, a match was taking place between two teams in the First Division of the Thanet and District Saturday League, Punch & Judy v Minster FC. By the 80th minute, Minster were two goals ahead and there had been animosity between certain players throughout the game.

With ten minutes remaining, Minster’s Christopher Bygraves got the ball about seven yards from the opposition’s goal and scored with his left foot. After he shot, Punch & Judy’s Mark Barnes came lunging in from behind. There was a snapping noise and Bygraves collapsed. Barnes got up and said, “Have that.” He was immediately sent off. Bygraves suffered serious injury to his right ankle.

Barnes was prosecuted for causing grievous bodily harm for the horrendous tackle and was convicted in the Canterbury Crown Court. He was given a community punishment order for 240 hours and was ordered to pay £2,609 to the victim, at £20 per week.

But his appeal was allowed. The Court of Appeal ruled the conviction was unsafe because it had followed a direction from the trial judge that wasn’t adequate. It should have been pointed out to the jury, for example, that even if the offending contact was a foul, it was still necessary for them to determine whether it was “something quite outside what could be expected to occur in the course of a football game”.

Lord Woolf, then Lord Chief Justice, said that for public policy reasons it was possible for consent to be a defence to what would otherwise be assaults, as in surgery or boxing. The players in contact sports consent to contact “even if, through unfortunate accident, injury, perhaps of a serious nature, may result”. But footballers don’t consent to being “deliberately punched or kicked and such actions constitute an assault”.

Whether misconduct in sport is bad enough to be criminal depends on all the circumstances. The law says you need to consider “the type of the sport, the level at which it is played, the nature of the act, the degree of force used, the extent of the risk of injury, [and] the state of mind of the defendant”.

In 2004, a Cambridgeshire village cricket match between Elsworth and Cambridge St Giles descended into something that was decidedly not cricket.

Joshua Fay, 14, was hurt after being attacked by a batsman he had just bowled out. He claimed that Michael Butt, 32, hit him with his bat and repeatedly punched him seconds after he had celebrated his dismissal. Cambridge Crown Court was told that Butt thought that Fay had called him a “tosser” under his breath.

Joshua’s father, Edward Fay, was hit by Butt after striding on to the field to defend his son. Joshua said of Butt: “He completely lost it. Something must have happened to him before. He just flipped.”

Butt was acquitted of affray but admitted the assault on Joshua and was sentenced to 175 hours community work and ordered to pay £200 compensation. "Somebody once said that the Battle of Waterloo was won on the playing fields of Eton," Judge Gareth Hawkesworth noted when giving sentence. “It is a saying”, he continued, “which I have never fully understood because as far as I am concerned war has no place on the playing field and it had no place here."

The essence of all competitive sport, including boxing and fencing, is that it’s a civilised substitute for real hostility. Because it’s conducted according to rules, sport sets us above savagery. And the sports’ rules that mark such important boundaries must be patrolled by the criminal law.

Professor Gary Slapper is Director of the Centre for Law at The Open University

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