DRS and Umpire's Call: Why the "Soft Signal" Still Matters in Cricket

What is DRS and Hawk-Eye?

The Decision Review System allows players to question an on-field umpire’s call by using technology. Each team receives a limited number of reviews per innings, which forces careful use. Once a review gets requested, third umpires rely on several tools, with ball tracking playing the biggest role in leg-before-wicket cases.

Hawk-Eye tracks the ball from release to impact and then projects its expected path after it strikes the pad. Cameras around the ground collect data points, and software builds a predicted trajectory. That projection helps officials judge events that the naked eye cannot fully confirm at match speed.

The Three Critical Zones in LBW Decisions

Every LBW review passes through three fixed checkpoints. Each one must satisfy the law before a dismissal stands.

• Pitching Zone: Officials first check where the ball landed. The delivery must pitch in line with the stumps or on the legal side allowed by the laws. If it lands outside that area, the batter is not out, and no further checks apply.
• Impact Zone: Next comes the point of contact between ball and pad. The system checks whether an impact occurred in line with the stumps. Contact outside the line often favors the batter, especially when the on-field call says not out.
• Wickets Zone: The final stage looks at what would have happened next. Hawk-Eye estimates whether the ball would have hit the stumps. Only when the projected path shows a clear hit does DRS support an out decision.

Together, these zones create the structure behind every LBW review. Understanding how they interact explains why some calls feel obvious while others end with an umpire’s call and continued debate.

Margin of Error and Predictive Path

Once the ball strikes the pad, its future path no longer exists in reality. Hawk-Eye reconstructs that path using speed, angle, bounce, and spin recorded before impact. From that data, the system predicts where the ball would have travelled next. Prediction always includes a margin of error, even with high-speed cameras and advanced models.

Umpire’s call exists to respect that uncertainty. In borderline cases, technology signals a possible outcome but stops short of full confidence. The message stays clear: evidence points one way, but not strongly enough to overturn a human decision made in real time. Rather than pretend precision where none exists, the system defers to the umpire.

The 50% Rule Explained

A clear numerical threshold governs these calls. For DRS to reverse an on-field decision, more than half of the ball must lie within the key zone under review. That zone could involve impact in line with the stumps or projected contact with the wickets.

When less than 50% of the ball overlaps that area, the verdict becomes an umpire’s call. The original decision stands because the margin falls inside the accepted error range. The benefit of the doubt remains with the on-field umpire, not the technology. This rule prevents marginal projections from rewriting decisions based on guesses rather than certainty.

Scenario A: Pitching Zone (No Umpire's Call)

The pitching zone leaves no room for interpretation. Hawk-Eye checks where the ball lands and gives a clear answer. The delivery either pitches in line with the stumps or it does not. Since this part relies on an actual contact point rather than prediction, the umpire’s call never applies here. A ball pitching outside the allowed area immediately rules the batter safe, no matter what happens afterward.

Scenario B: Impact Zone

Impact decisions often frustrate viewers because they sit right on the edge. An umpire may judge that pad contact happened outside the line and signal Not Out. When ball tracking later shows the ball brushing the line but not by enough margin, the system cannot overturn the call. Less than half of the ball in line triggers the umpire’s call, which means the original decision stays. Technology acknowledges the contact but lacks enough certainty to change the verdict.

Scenario C: Wickets Hitting

Most controversies come from the wicket-hitting stage. An umpire may give Out based on live judgment, and Hawk-Eye later shows the ball clipping the bails by a narrow margin. In that case, the decision remains Out. If the umpire had originally given Not Out, the same visual would protect the batter instead. Identical graphics can lead to opposite results, not because the system is inconsistent, but because it defers to the on-field call when certainty stays below the required level. That balance explains why the umpire’s call continues to divide opinion.

Why Reviews Are Retained

Under ICC playing conditions, a team does not lose its review when the final verdict comes back as Umpire’s Call. The logic stays practical. The review shows that the call sat on a very fine margin, where technology could not clearly prove the on-field umpire wrong. Since the challenge was justified, the review is retained.

A review is lost only when DRS shows a clear error by the player or captain. Examples include pitching clearly outside the line, impact well outside off stump, or the ball missing the stumps by a visible gap. In those cases, the system delivers a decisive answer, and the team pays the price by losing a review.

This rule encourages teams to challenge close calls without fear. Captains know that borderline decisions do not punish them, which keeps reviews active deeper into the match and preserves balance between technology and on-field judgment.

Virat Kohli and the "Stumps" Argument

Virat Kohli has repeatedly questioned the logic behind the umpire’s call, especially in cases where ball tracking shows even the slightest contact with the stumps. His argument focuses on clarity rather than probability. If technology confirms that the ball would touch the wicket, even by 1%, he believes the batter should be given out, without relying on the original on-field decision.

From this perspective, percentages feel artificial. A delivery that clips the bails by a fraction still hits the stumps, and for many players, that fact alone should decide the outcome. Kohli and others see the current rule as protecting batters through technical margins instead of rewarding accurate bowling. This view continues to fuel debate whenever a replay shows the ball barely brushing the wicket, but the decision stays unchanged.

The Technology Limitation Argument

Supporters of the current rule point to the limits of ball-tracking technology. The predictive path shown by Hawk-Eye is still a calculation based on speed, angle, and bounce, not a recorded fact after impact. Small variations in seam position or surface contact can change the real outcome, even if the graphic looks precise.

Because of that uncertainty, defenders argue that the on-field umpire must stay central to the decision. Until technology can guarantee 100% accuracy, the original call acts as a safety net. Umpire’s call exists to balance data with judgment, keeping human authority in place when the margin sits too close to certainty.