Mike Amos posed a problem:
Declarer's RHO now asks "Can I see that one again?"
"Nope" everyone agrees, you've quitted your card (There was a well trained TD at the table )
"We'd better call the TD then. I'm not sure but it's possible that I've revoked"
How should the TD proceed in this situation?
I have said many times that a TD should not look at a player's hand during the play of the hand. There are two reasons for this: TDs should never make judgement rulings quickly, and TDs can easily give information about the hand away to the whole table.
Now I am pleased that Mike has come up with an exception for me. In this case the TD should look at the player's hand. Why? Because none of my worries apply.
The TD will find out for himself without exposing a card whether the card led is of the same suit as the possible revoker's card. He now looks at possible revoker's hand to see whether it is a revoke. Suppose a heart was led, and possible revoker has played a diamond. He looks at the player's hand: all he is looking is to see whether there is one or more hearts in it. So no judgement is involved.
Aha, you say, but he will be giving information away as to whether this player has a heart. True, but it is information to which the table is entitled: they are all allowed to know whether the card constituted a revoke. So, if there is a heart in the hand the TD says "There is an unestablished revoke: you are required to correct the revoke card to one of the suit led."
Of course now revoker asks to see the trick so he knows what to play! Is he allowed to?
I have already explained that the Director should examine the card led, the card played by the defender and the rest of the defender's hand. He should do so without exposing a card and then either tell the players to continue since there was no infraction or say there was a revoke and require it to be corrected under L62A.
Now comes the question of whether the trick should be turned up, completely or partially, or in such a way that only the revoking player sees it. I have seen arguments that all cards should be faced because anything else is impractical or liable to create unauthorised information. There has also been an argument that they should all be turned face up because Law 66C gives the Director the right to do so.
Neither argument satisfies me. I should prefer to see a law that requires the cards and in my view there is one: Law 65A. When four cards are played to a trick they are turned face down. But once one is withdrawn to correct a revoke there only remain three cards played to the trick. Thus Law 65A no longer applies and the cards should be faced.
Note that it makes more sense still to face them once it is realised that if a card has been played by the non-offending side after the revoke card it can be changed under Law 62C. This could happen if the revoker had played second to the trick, or if declarer had led to the next trick. In fact the procedure is a normal one once an unestablished revoke is corrected: only the element of doubt over the revoke made the case unusual.