Traditionalists and progressives often disagree about the role of instant replay in professional sports. According to the sports traditionalist, human error has always been a component of sport. If an official misses a call, then that’s just part of the game. Progressives, on the other hand, believe it is more important to get the call right.
Different sports have adopted the use of instant replay to varying degrees The National Football League (NFL) exercises a challenge system that allows coaches to call for an examination of questionable plays. This challenge is typically made by throwing a red flag onto the field. Each team is allowed two such challenges, and if the challenge is overruled the team is charged with a timeout. As of 2011, only the official “replay assistant” can call for a replay on scoring plays, during overtime, or following the two-minute warning during each half.
In the National Basketball Association (NBA), instant replay is used to confirm if a shot is taken in time, to verify if two or three points should be awarded for a basket, and to determine which players should be ejected from the game due to brawls or fouls
Major League Baseball (MLB) has so far resisted using instant replay to any significant extent. While there isa movement urging a broader use of instant replay, right now it is primarily used to determine home runs and foul balls.
The National Hockey League (NHL) has a replay system that allows officials to “go upstairs” to confirm or challenge an on-ice call pertaining to a specified list of reviewable situations, mostly concerning the scoring of goals Alternatively, if the off-ice officials examining replay notice a missed call on a reviewable play, they can call down to the ice to correct the call. This must happen before the next face-off, though, or the on-ice call stands.
Though many concede that the NHL makes the best use of instant replay among the four major professional sports, the sport that does it better than any other is likely tennis. With the Hawk-Eye and Mac CAM technologies, replays are available quickly and accurately. As an added plus, the in-stadium fans are able to participate by viewing the computer-generated instant replay at the same time as the officials. Players are allowed up to three unsuccessful challenges per set (plus a fourth in a tie-break) to address disagreements regarding in-or-out calls by umpires.
While replays are impractical when it comes to subjective calls by officials, they can be very useful for objective calls such as goals and home runs, inbounds or out of bounds. With the technology available today, missed calls are being captured on high-definition cameras and replayed online and on highlight shows. As a result, these calls are becoming an embarrassment to the officials and the leagues. It appears inevitable that even the most resistant leagues will eventually adopt an instant replay system that will address most if not all objective calls.