PARIS, June 8 – "The ref was biased!"How often have you heard that accusation, from a manager, player or fan, incensed by a penalty, red card or extra minute of injury time that helped the other side to score?
Professional referees are quick to throw back the charge as wrong, a slur or sour grapes.
But over the past decade, scientific studies have highlighted how the man in the middle can be swayed, albeit unconsciously, by crowd pressure.
In a landmark study, British researchers examined the effect of crowd noise on referee decisions.
They asked 40 county-level refs, their experience ranging from newly qualified to over 40 years, to assess a video of 47 challenges or incidents in a 1999 Liverpool-Leicester match.
Twenty-two of the volunteers watched the video with crowd noise — with the Kop in full voice — but without commentary, while 18 viewed it in silence.
Those who watched in silence were more certain about their decision, awarded more fouls against the home team and were likelier to determine that no foul had taken place.
Those who listened with the volume on were not likelier to award fouls against Leicester.
But, compared with the "silent" group, they did award 15.5 percent fewer fouls against Liverpool.
And their decisions, it turned out, closely mirrored those of the match referee.
"The presence or absence of the crowd noise did have a dramatic effect," said University of Wolverhampton professor Alan Nevill, who led the research.
German statisticians analysed 3,519 German first division matches played between 1992 and 2003, accessing a data bank compiled by the company Innovative Media Technology and Planning (IMP).
IMP compiles reams of match facts and also gives its opinion as to whether the ref’s decisions were correct.
It disputed five percent of decisions on goals that were awarded to the home team, but only four percent of goals awarded to the away side. If so, the home side had a 25-percent greater chance of getting a borderline goal decision in its favour.
As for penalties, only 65 percent of home team penalties were considered justified by IMP, compared to 72 percent for penalties awarded to the visitors.
Just as intriguing was this: refs were likelier to make a disputed ruling and award more stoppage and injury time to home teams trailing their opponents when the game was played in a stadium that had no athletics track.
"Probably the referee is subjected to greater social pressure if the spectators are right next to the pitch," remarked University of Bonn investigator Thomas Dohmen.
FIFA says World Cup refs are the cream, undergoing arduous training to ensure decisions are fair.
"Referees are accustomed to being in front of large crowds, and the training process for elite referees is a long one," it said an emailed reply to AFP.
"A referee will not be exposed to a match in front of 50,000 spectators or more immediately.
"Furthermore, and in particular for the FIFA World Cup, the referees benefit from the support of a wide variety of experts. One such focal area is that of mental preparation, where referees prepare for the different scenarios they will encounter during a match at this level."
But here’s the question: Can referees avoid human instinct?
Dutch researchers at Erasmus University this year analysed data from all fouls in seven seasons of the UEFA Champions League, the Bundesliga and the last three World Cups — a total of 123,844 incidents of whistle-blowing.
When it came to ambiguous fouls, players who were taller were considered likelier to have caused the offence and shorter players were likelier to be considered a victim. This was also the case even when no fouls had been committed.
The findings tally with evolutionary research: we associate taller people with aggression or domination.