Rules of Cricket

Officials

Umpires

A cricket match is adjudicated by two umpires, who make all decisions on the field. The umpire's decisions are final and players are not entitled to question them in any way.

During the bowling of a ball, one umpire stands behind the non-striker's wicket, ready to make judgements on LBWs and other events requiring a decision. The other umpire stands on the striker's popping crease, about 20 metres (20 yards) to one side (usually the leg side, but not always), ready to judge stumpings and run-outs at his end. The umpires remain at their respective ends of the pitch, thus swapping roles every over. The umpires swap ends after each side has completed one innings.

Whenever any decision involving the fall of a wicket is in any doubt whatsoever in an umpire's mind, the umpire must rule in favour of the batsman.

If a live ball hits an umpire, it is still live and play continues. If it lodges in an umpire's clothing, it becomes dead.

Appeals

Whenever a batsman may be out, he is entitled to wait for a decision from the appropriate umpire before leaving the field. In many cases, such as being bowled or most catches, it is obvious to all that the batsman is out and he usually leaves the field without waiting for the umpire's decision.

Some cases, such as very fine edges of the ball off the bat caught by the wicketkeeper, or all LBWs, are not obvious. In such cases, the umpire does not make a decision unless the fielding team appeal to the umpire for a decision. This is conventionally in the form of the question "How's that?" - often shouted with enthusiasm by multiple members of the fielding team as "Howzat?!"

Following an appeal, the umpire will make a decision and all players must abide by it.

Extra Detail: Umpires Signals

The umpires signal various events with gestures, as follows:

Out. The umpire raises one hand above his head, with the index finger extended.
Not Out. There is no formal signal to indicate that a batsman is not out. The umpire usually shakes his head 'no'.
Four. The umpire extends an arm horizontally and waves it briefly back and forth in a horizontal arc.
Six. The umpire raised both arms straight over the head.
No Ball. The umpire holds one arm out horizontally.
Wide. The umpire holds both arms out horizontally.
Byes. The umpire raises one arm over the head, palm open.
Leg Byes. The umpire raised one leg and taps the knee, thigh, or shin with one hand.
Dead Ball. If an umpire has to signal dead ball to prevent the players from assuming that the ball is still alive, he waves both arms across each other in front of his abdomen.
One Short. The umpire touches the tip of one hand to the same shoulder.
Third Umpire. If an umpire wishes the third umpire to make a decision based on a TV replay, he draws a large square shape in the air with both hands, spreading them out high in the air in front of him, bringing them down, and then together again.

Extra Detail: Third Umpire

If the technology is available for a given match, a third umpire may be used. He sits off the field, with a television replay monitor. If an on-field umpire is unsure of a decision concerning certain events, he may signal for the third umpire to view a television replay. The third umpire views a replay, in slow motion if necessary, until he either reaches a decision or decides that he cannot make a clear decision. He signals the result to the on-field umpire, who must then abide by it. If the equipment fails, the third umpire signals no decision.

The type of events that may be referred to the third umpire are explicitly restricted, and the list is updated from time to time following administrative reviews. Currently, only the following events may be referred to the third umpire:

run outs,
stumpings,
hit wickets,
whether or not a catch has carried to a fielder before hitting the ground,
whether or not a ball or fielder has touched the boundary.

The following events are among those currently prohibited from being referred to the third umpire:

LBWs,
whether or not the batsman has hit the ball for a catch.

Extra Detail: Match Referee

Professional level cricket matches are presided over by a match referee, who watches from outside the field. The referee makes no decisions of relevance to the outcome of the game, but determines penalties for breaches of various rules and misconduct. In professional games, these penalties are monetary fines and/or suspension from subsequent matches.