This was invented for the Atlanta games to make boxing matches fairer.Four judges, one at each corner of the ring, operate the machine by pressing a button each time a decisive punch is given. So that the right boxer is credited with the punch, three of the four judges must activate their machine in the same second.Juan Antonio Samaranch himself pushed for this machine to be introduced. In doing so, boxing, which was threatened with exclusion from the programme after the Seoul games, has been restored to its rightful place. During the Sydney 2000 Games, the officials who refereed the Olympic competitions were filmed by "spy cameras" positioned at the four corners of the ring. This was done as a trial to assess the referees' subjectivity with the aim of putting an end to controversial decisions. The filmed referees were allowed to commit three or four errors, but no more. One of them has been barred. However, this did not prevent Cuban president Castro, a great boxing fan, to denounce the injustices he said "his" boxers had been subjected to during the Sydney Olympics.