[Fluffy]

♠KQxx
♥x
♦KQ109xxx
♣x

♠Jx
♥KQxx
♦Axxx
♣Axx


Today at the club I was sitting south and bid:

1♦-(1♠)-5♦-all pass

LHO led a club, I won, played a trump to dummy (falling 1-1) and a trump to hand (club pitches).

Next I led ♥Q from hand to give LHO a (very rare) chance to duck. LHO hesitated for about 5 seconds, and pitched ♠4. ♥Q won the trick and then she realised that ♥Q wasn´t a diamond.

I think since she didn´t play to next trick the revoke isn´t stablished, but what about the UI that partner cannot beat ♥Q?

[campboy]

Interesting situation. I can't find anything which makes partner's card UI when correcting the revoke, but I might be missing something.

If I felt there was a reasonable chance that she might have ducked had she followed suit I would adjust the score using law 23. It's quite similar to an Alcatraz coup so I think "could have known" applies here too.

[Vampyr]

 campboy, on 2011-November-21, 17:20, said:

Interesting situation. I can't find anything which makes partner's card UI when correcting the revoke, but I might be missing something.

Well, there is:

Quote

16C3D. Information from Withdrawn Calls and Plays

When a call or play has been withdrawn as these laws provide:

1. For a non-offending side, all information arising from a withdrawn action is authorized, whether the action be its own or its opponents’.

2. For an offending side, information arising from its own withdrawn action and from withdrawn actions of the non-offending side is unauthorized. A player of an offending side may not choose from among logical alternative actions one that could demonstrably have been suggested over another by the unauthorized information.

Maybe RTFLB before/instead of answering a question on the Laws?

[campboy]

That law says the ♠4 is UI to Fluffy's RHO, but so what? The question here is whether the low heart RHO played (which has not been withdrawn) is UI to LHO when she corrects her revoke.

[blackshoe]

I'm afraid the fact that RHO can't beat the ♥Q is AI (Law 16A1{a}). I would apply Law 23 if the NOS are damaged by the correction of the revoke.

[Vampyr]

 campboy, on 2011-November-21, 18:45, said:

The question here is whether the low heart RHO played (which has not been withdrawn) is UI to LHO when she corrects her revoke.

Oh I see. Sorry. I hadn't understood the question.

[pran]

 blackshoe, on 2011-November-21, 21:02, said:

I'm afraid the fact that RHO can't beat the ♥Q is AI (Law 16A1{a}). I would apply Law 23 if the NOS are damaged by the correction of the revoke.

The information that East (apparently) could not beat the ♥Q derives to West from illegal play (by West) that has not been accepted so it is not "protected" by Law 16A1{a}, nor by any other law in the book. Hence this information is UI to West.

But West did not "duck" the ♥Q, he discarded on a "trump", so I would still allow him to rectify his revoke by playing the ♥A to this trick.

Eventually the Director should try if Law 23 (or even Law 12A1) is appliccable to this irregularity.

[blackshoe]

How does it "derive" from West's play? It was subsequent, not consequent.

[pran]

 blackshoe, on 2011-November-22, 08:23, said:

How does it "derive" from West's play? It was subsequent, not consequent.

If West had covered the Queen with his Ace he would have been unable to tell who holds the King when East just followed suit.
When West did not cover the Queen and East just followed suit then West knows that East cannot possibly hold the King.

If West plays the Ace he just might drop a stiff King from East, and if West plays a low heart he may completely lose a trick for his Ace. Now he has clarified that he can play the Ace with no risk of finding a (stiff) King in East. Hence his knowledge of the location of the King is a consequence of his illegal play.

This kind of plot ("how to locate a key card without the risk of losing a trick") has been a theme in several excercises for Norwegian Directors. (Usually the plot is performed by Declarer in these excercises.)

[iviehoff]

 blackshoe, on 2011-November-22, 08:23, said:

How does it "derive" from West's play? It was subsequent, not consequent.

The full wording of 16A(1)(a) is

A player may use information in the auction or play if:
(a) it derives from the legal calls and plays of the current board (including illegal calls and plays that are accepted) and is unaffected by unauthorized information from another source

East's play of the low heart is affected by the UI of West's to-be-withdrawn revoke of the spade, which is therefore UI to E. So E's choice of play is not AI to West.

Pran mentions the possibility of dropping a singleton king by E, a rather remote possibility with a singleton on table and no one bidding hearts. But it may simply be valuable to the defence that E rather than W wins the trick at this point, if he is able to. But there are no tenace positions to favour a lead from E, and West not looking for a ruff either, or needs an entry later, or needs to protect against a squeezes or end-plays. So there is no cost at all to W playing the A here, and given the risk S has the K, there is surely no LA to doing so: in other words, S's choice of the Q will fool no one here. So I think on this occasion W is free to correct his revoke to the A. The same argument dismisses any case for an adjustment under Law 23, on this hand.

[pran]

 iviehoff, on 2011-November-23, 03:34, said:

[...]
Pran mentions the possibility of dropping a singleton king by E, a rather remote possibility with a singleton on table and no one bidding hearts. But it may simply be valuable to the defence that E rather than W wins the trick at this point, if he is able to. But there are no tenace positions to favour a lead from E, and West not looking for a ruff either, or needs an entry later, or needs to protect against a squeezes or end-plays. So there is no cost at all to W playing the A here, and given the risk S has the K, there is surely no LA to doing so: in other words, S's choice of the Q will fool no one here. So I think on this occasion W is free to correct his revoke to the A. The same argument dismisses any case for an adjustment under Law 23, on this hand.

I agree.
My comments reflected a general principle of which the Director should be aware.

Knowledge of this principle is the reason I am vigilant when a player revokes and then rectifies his revoke before it becomes established but after he has seen subsequent plays by opponents or partner. Knowledge derived from such subsequent plays should be ruled UI to the offender.

[campboy]

 pran, on 2011-November-23, 03:47, said:

Knowledge of this principle is the reason I am vigilant when a player revokes and then rectifies his revoke before it becomes established but after he has seen subsequent plays by opponents or partner. Knowledge derived from such subsequent plays should be ruled UI to the offender.

I do not believe this is consistent with the laws since those subsequent plays were legal and have not been withdrawn.

[iviehoff]

 campboy, on 2011-November-23, 05:50, said:

I do not believe this is consistent with the laws since those subsequent plays were legal and have not been withdrawn.

Do you disagree with what I said at #10?

[campboy]

 iviehoff, on 2011-November-23, 05:57, said:

Do you disagree with what I said at #10?

Yes. The *information* that East played a low heart is unaffected by UI, since West doesn't have any. The fact that the *play* might have been affected by UI is irrelevant; the law talks about the information being unaffected.