82. When any one, except dummy, plays two or more cards to the same trick and the mistake is not corrected, he is answerable for any consequent revokes he may have made. When during the play the error is detected, the tricks may be counted face downward, to see if any contain more than four cards; should this be the case, the trick which contains a surplus card or cards may be examined and the card or cards restored to the original holder, who (not being dummy) shall be liable for any revoke he may meanwhile have made.
THE REVOKE[[27] ]
83. A revoke occurs when a player, other than dummy, holding one or more cards of the suit led, plays a card of a different suit. It becomes an established revoke if the trick in which it occurs is turned and quitted by the rightful winners (i.e., the hand removed from the trick after it has been turned face downward on the table); or if either the revoking player or his partner, whether in turn or otherwise, lead or play to the following trick.
84. The penalty for each established revoke is:—
(a) When the declarer revokes, his adversaries add 150 points to their score in the honor column, in addition to any penalty which he may have incurred for not making good his declaration.
(b) If either of the adversaries revoke, the declarer may either add 150 points to his score in the honor column, or may take three tricks from his opponents and add them to his own. Such tricks may assist the declarer to make good his declaration, but shall not entitle him to score any bonus in the honor column, in the case of the declaration having been doubled or re-doubled.
(c) When more than one revoke is made by the same side during the play of the hand the penalty for each revoke after the first, shall be 100 points in the honor column.
A revoking side cannot score, except for honors or chicane.
85. A player may ask his partner if he has a card of the suit which he has renounced; should the question be asked before the trick is turned and quitted, subsequent turning and quitting does not establish a revoke, and the error may be corrected unless the question is answered in the negative, or unless the revoking player or his partner has led or played to the following trick.
86. If a player correct his mistake in time to save a revoke, any player or players who have followed him may withdraw their cards and substitute others, and the cards so withdrawn are not exposed. If the player in fault is one of the declarer's adversaries, the card played in error is exposed and the declarer may call it whenever he pleases; or he may require the offender to play his highest or lowest card of the suit to the trick, but this penalty cannot be exacted from the declarer.