Third Umpire Decision Protocols in Cricket: A Complete Explainer

The third umpire is cricket's video official. Sitting in a booth with a bank of monitors, ball-tracking software and slow-motion replays, they rule on run-outs, stumpings, close catches, boundary touches and front-foot no-balls. On-field umpires call them via a hand-drawn TV signal (a square traced in the air) or, under the Decision Review System (DRS), a player may trigger the review with the T-sign. Every decision follows a documented protocol under MCC Laws and ICC playing conditions.

When is the third umpire called in?

Four situations trigger a third-umpire check. First, on-field umpires can refer any close run-out or stumping by drawing the TV square. Second, they can refer a low catch to verify whether the ball carried cleanly. Third, fielders or batters can call for a DRS review on LBW, caught-behind, bat-pad and some no-ball decisions. Fourth, since 2020, every front-foot no-ball is automatically checked by the third umpire at international level, relieving the square-leg umpire of that duty.

Boundary decisions, a fielder's contact with the rope, and overthrow distances can also be referred. Increasingly, the third umpire proactively intervenes for obvious errors: a missed no-ball that dismisses a batter, or a clear edge the on-field umpire never saw.

The tech stack: Hawk-Eye, UltraEdge, Snicko and ball-tracking

The third umpire is only as good as the tools available. At major tournaments, the booth includes:

• Hawk-Eye or a similar ball-tracking system, used for LBW predictions under DRS. Six cameras triangulate the ball's flight, pitch-point, impact-point and projected path to the stumps.
• UltraEdge / Real-Time Snicko to detect fine contact between bat and ball. Audio spikes are synchronised to slow-motion frames.
• Multi-angle super slow-motion cameras running at up to 340 frames per second.
• Hot Spot, an infrared system that reveals friction marks from ball-on-bat contact. It is expensive and not used at every venue.

Under ICC protocol, if ball-tracking is unavailable (for example due to a broken camera), the on-field decision stands and the reviewing side does not lose a review.

DRS review rules: how the "umpire's call" works

A side gets two unsuccessful reviews per innings in Tests and ODIs; in T20s it is typically one or two depending on playing conditions. An LBW review has three questions: pitching (was it outside leg stump?), impact (was it outside off while playing a shot?) and wickets hitting (is more than 50 per cent of the ball clipping the stumps on the predicted path?). If all three go in the bowler's favour, the batter is out.

Umpire's call is the tie-breaker. If the prediction is marginal — less than half the ball hitting the stumps, or the impact is borderline — the on-field decision stands. The reviewing side does not lose their review in an umpire's-call scenario. The ICC tightened the wicket-zone threshold in 2021 to reduce marginal overturns, a change that drew both praise and criticism from captains who felt the system had become stingier.

Run-outs, stumpings and the soft-signal debate

For run-outs and stumpings, the third umpire looks for conclusive evidence that the stumps were broken before the bat or foot grounded behind the crease. Any daylight between bat and line, with at least one bail dislodged from the groove, is out. Stumpings have a clearer geometry: once the wicketkeeper breaks the stumps and the batter is out of the crease without the bat grounded, it is out.

Catches have been trickier. Until 2023, on-field umpires gave a soft signal (their preferred decision) on low catches before going upstairs. The ICC scrapped soft signals in Tests from June 2023. Now the third umpire decides from scratch, and if replays are inconclusive, the benefit goes to the batter. This removed the strange situation where clear high-definition replays could not overturn a guess made at ground level.

Front-foot no-balls and the 2020 automation shift

After a string of missed no-balls in high-stakes matches (remember the Mumbai Indians vs Royal Challengers Bangalore no-ball controversy in IPL 2019?), the ICC and BCCI pushed the check to the video booth. Now, after every delivery, the third umpire has a few seconds to scan the front-foot landing. If any part of the front foot is behind the popping crease at release, the delivery is legal; if none of the foot is behind the line, it is a no-ball and the square-leg umpire is notified in real time. This system is live across IPL, WPL and international cricket.

What the third umpire cannot do

The third umpire cannot overrule a wide, a leg-bye or a front-foot no-ball call that was not referred within the review window. They cannot award runs retrospectively beyond the next delivery. They cannot penalise slow over rates — that is the match referee's job. And they cannot initiate DRS themselves beyond the explicit scenarios listed in playing conditions.

FAQ

Q: Who pays for the third umpire and DRS tech? A: At bilateral series, the host board typically funds the standard kit. At ICC events, the ICC funds a uniform DRS package across all venues, including Hawk-Eye, UltraEdge and full camera coverage.

Related reading

• Front Foot No-Ball Rule: Cricket Technology Explained
• Mankad Runout Rule: History and 2026 Debate
• Free Hit Rule: Origin, Law and Strategy