Laws of Cricket 1980 Code - Law 28
1. Wicket Down
The wicket is down if
a. Either the ball or the striker's bat or person completely removes either bail from the top of the stumps. A disturbance of a bail, whether temporary or not, shall not constitute a complete removal, but the wicket is down if a bail in falling lodges between two of the stumps.
b. Any player completely removes with his hand or arm a bail from the top of the stumps, providing that the ball is held in that hand or in the hand of the arm so used.
c. When both bails are off, a stump is struck out of the ground by the ball, or a player strikes or pulls a stump out of the ground, providing that the ball is held in the hand(s) or in the hand of the arm so used.
2. One Bail Off
If one bail is off, it shall be sufficient for the purpose of putting the wicket down to remove the remaining bail, or to strike or pull any of the three stumps out of the ground in any of the ways stated in 1 above.
3. All the Stumps Out of the Ground
If all the stumps are out of the ground, the fielding side shall be allowed to put back one or more stumps in order to have an opportunity of putting the wicket down.
4. Dispensing with Bails
If owing to the strength of the wind, it has been agreed to dispense with the bails in accordance with Law 8 Note (a) (Dispensing with Bails) the decision as to when the wicket is down is one for the umpires to decide on the facts before them. In such circumstances and if the umpires so decide the wicket shall be held to be down even though a stump has not been struck out of the ground.
Note
1. Remaking the Wicket
If the wicket is broken while the ball is in play, it is not the umpire's duty to remake the wicket until the ball has become dead - see Law 23 (Dead Ball). A member of the fielding side, however, may remake the wicket in such circumstances.
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