Leg before wicket (lbw) is one of the ways in which a batsman can be dismissed in the sport of cricket. The basis of the law is that, following an appeal by the fielding side, the umpire may rule a batsman out lbw if the ball would have struck the wicket but was intercepted by any part of the batsman except his bat. The umpire's decision will depend on a number of criteria, including where the ball pitched, whether the ball hit in line with the wickets and whether the batsman was offering a shot.
Lbw first appeared in the laws in 1774, as batsmen began to use their pads to prevent the ball hitting their wicket. Over several years, refinements were made to clarify where the ball should pitch and to remove the element of interpreting the batsman's intentions. The 1839 version of the law used a wording that remained in place for nearly 100 years. However, from the latter part of the 19th century, batsmen became increasingly expert at "pad-play" to reduce the risk of their dismissal. Following a number of failed proposals for reform, in 1935 the law was expanded, such that batsmen could be dismissed lbw even if the ball pitched outside the line of off stump. Critics felt this change made the game unattractive as it encouraged negative tactics at the expense of leg spin bowling.
After considerable debate and various experiments, the law was changed again in 1972. In an attempt to reduce pad-play the new version, which is used to this day, allowed batsmen to be out lbw in some circumstances if they did not attempt to hit the ball with their bat. Since the 1990s, the availability of television replays and, later, ball-tracking technology to assist umpires has increased the percentage of lbws in major matches. However, the accuracy of the technology and the consequences of its use remain controversial.
In his 1995 survey of cricket laws, Gerald Brodribb states: "No dismissal has produced so much argument as lbw; it has caused trouble from its earliest days".[1] Owing to its complexity, the law is widely misunderstood among the general public and has proven controversial among spectators, administrators and commentators; lbw decisions have sometimes caused crowd trouble. Since the law's introduction, the proportion of lbw dismissals has risen steadily through the years. Statistics reveal that the probability of a batsman being dismissed lbw in a Test match varies depending on where the match is played and which teams are playing.