Inventor of Hawk-Eye says referral system proves worth

South Africa cricket coach Mickey Arthur has become the latest prominent figure in the sport to express reservations about the Hawk-Eye technology which is now being used to check leg-before-wicket decisions.                                           

"I'm not 100% convinced about the predictive element of Hawk-Eye and I don't think many players are either," Arthur wrote in the February issue of Wisden Cricketer which goes on sale this Friday.                                           

Hawk-Eye uses data produced by video cameras to predict whether a ball that has hit the batsman on the pads would have gone on to hit the stumps, the so-called lbw decision which can be among the most contentious in cricket. The technology is used in tennis to decide disputed line calls.                                           

In a telephone interview, Hawk-Eye's British inventor Paul Hawkins rejected the criticisms and said Hawk-Eye calculated the trajectory of a ball after it had bounced and hit the batsman's pad, based purely on the behaviour of that particular ball.                                           

"You only need about a foot (30 cm) to travel and you get an accurate prediction of the line, you need a little bit more to predict the height," he said.                                           

Hawkins said the umpires in each of the 10 tests in Australia and South Africa in which Hawk-Eye had been used by the third umpire in the Umpires Decision Review System to help determine lbw decisions believed each decision had been correct.                                           

"We have now 10 test matches and most of the referrals have been lbws. We have certainly got every single one right," he said.