Bridge & other card games/contract bridge
When it becomes apparent during the play that the players do not have an equal number of cards left, what is the proper decision: throw in the hand or play it with only 3 cards on the last trick? This can happen either due to a misdeal at the beginning or someone gathering up too many cards in a trick, thus leaving someone or the dummy short one card.
If the situation is a result of the cards being dealt incorrectly then the hand needs to be thrown in and dealt again. In this case, though, assuming that all 52 cards were dealt then if one player has too few cards another player should have an excess.
It is more likely that if one player is short near the end of the hand it is because he inadvertently played two cards to a previous trick. In this case Law 67 applies.
When one player is found, during play, to have fewer or more cards than all the other players, the previous tricks should be forthwith examined, face down; if a defective trick is discovered, the player with a correspondingly incorrect number of cards is held responsible. The defective trick is inspected face up and
(a) if the responsible player has not played to a subsequent trick, the defective trick is rectified as follows:
(i) if the offender has failed to play a card to the defective trick, he adds to that trick a card he can legally play.
(ii) if the offender has played more than one card to the defective trick, he withdraws all but one card, leaving a card he can legally play.
(iii) the non-offending side may, without penalty, withdraw any cards played after the irregularity and before attention was drawn to it; but the offending side may not withdraw cards that constitute legal plays, and any cards they withdraw may become penalty cards.
(b) after the responsible player has played to a subsequent trick, the ownership of the defective trick cannot be changed and
(i) if the offender has failed to play a card to the defective trick, he forthwith faces and adds a card to that trick, if possible one he could legally have played to it.
(ii) if the offender has played more than one card to the defective trick, he withdraws all but one card, leaving the highest card he could legally have played to that trick. A withdrawn card may become a penalty card; such a card is deemed to have belonged continuously to the offender's hand and failure to have played it to an earlier trick may constitute a revoke.