The DRS (Decision Review System) rule for LBW (Leg Before Wicket) involves a complex interplay between on-field umpires' decisions and technology, with "Umpire's Call" playing a crucial role. Here's a breakdown:
Understanding the LBW DRS Process
When a batter is given not out by the on-field umpire, the fielding team can opt to review the decision using DRS. Similarly, if the batter is given out, they can review the decision. The process involves:
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Ball Tracking Technology: This technology predicts the trajectory of the ball, including whether it would have hit the stumps. Key elements considered are:
- Point of Impact: Where the ball pitched. It must be within the pitching requirements for LBW (in line or outside off-stump, but not outside leg-stump).
- Impact with the Batter: Where the ball hit the batter's leg. This must be in line with the wickets, or the batter must have offered a shot to a ball pitching outside off stump.
- Wicket Prediction: Projecting the ball's path to determine if it would have hit the wickets.
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Umpire's Call: This is the most debated part of the LBW DRS rule. It applies when the ball-tracking technology shows that the ball is only marginally hitting the wickets.
The Umpire's Call Explained
- Wicket Hitting Zone: The area of the stumps considered for impact.
- 50% Rule: For the on-field umpire's decision to be overturned, ball-tracking must show that at least 50% of the ball's width needs to be hitting at least one of the three stumps. This is often visually represented as at least half the ball appearing to be within the 'wicket zone' on the review graphics.
- Stumping Zone: Some sources say at least part of the ball needs to hit the stumping zone.
Outcome Scenarios
The outcome of a DRS review for LBW depends on the level of certainty provided by ball-tracking:
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Decision Overturned: If the ball-tracking shows that the ball is clearly hitting the wickets (at least 50% of the ball hitting a stump) and other LBW conditions are met, the on-field umpire's decision is overturned.
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Umpire's Call Stands: If the ball-tracking indicates the ball is only marginally hitting the wickets (less than 50% of the ball hitting a stump), the original on-field decision stands. This means:
- If the umpire gave the batter out, the batter remains out.
- If the umpire gave the batter not out, the batter remains not out.
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Decision Upheld (Original Decision Confirmed): If the technology clearly supports the on-field umpire's original decision, the decision is upheld without relying on "Umpire's Call."
Controversies and Criticisms
The "Umpire's Call" has been a subject of much debate. Many argue that if ball-tracking shows the ball is going to hit the stumps, even marginally, the batter should be out. Critics believe it is inconsistent to allow the on-field umpire's original (possibly incorrect) decision to influence the outcome when technology is available to provide a more accurate assessment.
In summary, the DRS rule for LBW relies on ball-tracking technology, but incorporates "Umpire's Call" when the ball is only marginally hitting the wickets, leading to ongoing debate about its fairness and accuracy.
