Few things start more arguments than a leg before wicket decision. Fans groan, batters stare at the sky, and the commentators debate the finer points for ten minutes. The law is actually simple once you break it into three questions.
What LBW means
A batter is out leg before wicket when the ball would have gone on to hit the stumps, but their body, usually the pad, stopped it first. The batter’s legs are not allowed to act as a second set of stumps.
Question one: where did the ball pitch?
For a batter to be out, the ball must pitch in line with the stumps or on the off side. If it pitches outside leg stump, the batter cannot be out LBW, no matter how plumb the rest of the delivery looks. This is the first thing an umpire checks.
Question two: where was the impact?
The ball must hit the batter in line with the stumps. If the batter plays a shot, the impact can be anywhere in line, and also outside the line of off stump if they genuinely tried to hit the ball. If the batter offers no shot, the impact must be in line between wicket and wicket.
The no-shot condition is important. A batter who plays a shot and gets hit outside off stump cannot be given out. A batter who leaves the ball with the pad in the way is only in danger if the impact is in line.
Question three: would it have hit the stumps?
The umpire must decide that the ball would have gone on to hit the stumps. This is the part where technology now helps. Ball tracking predicts the path of the ball after it hits the pad, and shows whether it would have hit the stumps.
Umpire’s call
When a review shows the ball only clipping the stumps, the original decision stands. This is called umpire’s call. It exists because ball tracking is a prediction, and the margin for error is real. If the umpire gave the batter out, the ball clipping the stumps is not enough to overturn it. If the umpire gave not out, the same applies in reverse.
A quick checklist
Pitching in line or on the off side. Impact in line, or outside off if a shot was played. Hitting the stumps. If all three are yes, the batter is out. If any are no, they survive.
The next time a loud appeal goes up, run through these three questions. You will find you can predict the decision before the replay, and you will understand why even the best batters occasionally get a rough call.