Laws of Cricket 1947 Code - Law 39
The Striker is out "Leg before wicket" - If with any part of his person except his hand, which is in a straight line between wicket and wicket, even though the point of impact be above the level of the bails, he intercept a ball which has not first touched his bat or hand, and which, in the opinion of the Umpire, shall have, or would have, pitched on a straight line from the Bowler's wicket to the Striker's wicket, or shall have pitched on the offside of the Striker’s wicket, provided always that the ball would have hit the wicket.
Note on Law 39
1. A batsman is only "Out" under this Law if all the four following questions are answered in the affirmative.
a. Would the ball have hit the wicket?
b. Did the ball pitch on a straight line between wicket and wicket (and this case includes a ball intercepted full pitch by the striker), or did it pitch on the offside of the striker's wicket?
c. Was it part of the striker's person other than the hand which first intercepted the ball?
d. Was that part of the striker's person in a straight line between wicket and wicket at the moment of impact, irrespective of the height of the point of impact?
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