An untested new law - do we know what it means?

Brighton 2011 – Day 9

My article on insufficient bids appears in the bulletin today, but caused litte comment. Instead, to keep this blog on topic but away from Law 27; we had a ruling on a new part of the claim laws.

Apparently, declarer claimed the rest in a spade contract, with no statements, in something like this position:

	♠ Jxx
	♥ Jxx
	♦
	♣
♠ 9		♠
♥ 10x		♥ xx
♦ 8		♦ xx
♣ AK		♣ xx
	♠ 10
	♥ x
	♦ Q6
	♣ xx

The defenders did not accept the claim and instead play continued: diamond from West, won by South; a diamond from South, ruffed by West, and over-ruffed; and now declarer could ruff a heart and did have the rest. At some point the TD was called and he used Law 70D1:

In accordance with Law 68D play should have ceased, but if any play has occurred after the claim this may provide evidence to be deemed part of the clarification of the claim. The Director may accept it as evidence of the players’ probable plays subsequent to the claim and/or of the accuracy of the claim.

Although we know the background of this addition to the laws (“He claimed it on a double squeeze”) we have not had an test cases of the new law as written.

The TD ruled that the play subsequent to the claim provided sufficient evidence of how the defenders would play to award declarer the rest of the tricks. I felt that Law 70D1 should be used to extend the possible normal plays of the claimer: any line that the claim actual made subsequent to the claim should be regarded as normal. But I did not think the Law 70D1 should be used to restrict the possible normal plays by the non-claiming side. In this case there are a number of lines for the defence that result in a trick. Even if they don't lead a trump, they would still be awarded a trick if they are not made to ruff in on the second diamond.

To irrationality and beyond

Brighton - Day 3

Not a significant ruling but it does draw attention to variations in wording in the (claim) laws. which we do not know whether it is nuanced wording or inconsistent editing.

	--
	x
	Q 9 x
	Q
?		?
--		--
J x x ?		A 7 x ?
?		2
	--
	x x
	K 10 x
	--

Declarer (shown as South), in 4♥, leads ♣Q from dummy and RHO discards ♦7, then finds ♣2 in her hand. I am called: the ♣2 is played to the trick and ♦7 is a major penalty card (to be played at the first opportunity, etc.). Declarer ruffs and quits the trick but LHO is still thinking what to play to this trick. After a bit, while LHO is still thinking, declarer says it doesn't matter. I ask him if he is claiming (because otherwise I would ask him to let LHO think in peace) and declarer says "yes, I can play a diamond to the nine" (taking advantage of the major penalty card). "What if I play the jack" says LHO, "well then obviously ..." starts declarer.

The position is different from that where declarer plays a small diamond and calls for the nine before seeing LHO's card. In a claim, declarer will not be held to lines of play that are irrational (Law 70E1). So (obviously) declarer is allowed his claim for all but one of the remaining tricks (losing ♦A).

As noted in a previous post, the test in Law 70E is different from the rest of Law 70. Law 70E1 uses the word "irrational", a word that was removed from the footnote referred to by the rest of Law 70 (and by Law 71). What is the difference between not "normal" (including "play that would be careless or inferior for the class of player involved") and "irrational"; or was "irrational" left in Law 70E to avoid unweildy wording: "unless failure to adopt that line of play would be beyond careless-or-inferior"?.

Normal, irrational, likely, legal plays

The forums (RGB, IBLF, BLML, BBO) are awash with discussions of claims, as ever. I can not resist a posting on the different classes of plays that the (current) claim laws require a TD to consider.

1997 Laws

In the 1997 laws there is

• "normal" (Laws 69, 70 and 71), includes careless or inferior but not irrational (footnote 20);
• "irrational" (end of Law 70E), because of the footnote I had interpreted this as the opposite of normal (probably erroneously);
• "legal" (Law 71A), I think we understood this and, with the proper interpretation of Law 71, we did not need to distinguish this from "normal".

So, with my naive understanding of "irrational" in Law 70E, we only needed to understand what was or was not "normal", as in "normal play of the remaining cards" or "normal line of play".

2007 Laws

Now, in the 2007 laws there are again three different classes of plays, but now I think they are all independent.

• "likely" (Law 69B), a clear change from 1997;
• "normal" (Laws 70 and 71), includes careless or inferior (footnote 22);
• "irrational" (Law 70E1), without this word occurring in the footnote.

The change from "normal" to "likely" in Law 69, and the removal of "irrational" from footnote 22, indicates to me that there are now three independent tests to be applied in Laws 69, 70, and 71. For now all I can do is record the different terms, we will have to await experience, case law, and interpretation to distiguish them.

Bounded rationality

It is clear in that "irrational" in the 1997 laws could not interpreted literally, leading the Ace from A10xx opposite KQ9xx was normal but also irrational. A friend, bridge partner, and mathematician who mixes with economists, introduced me to the concept of bounded rationality which is used by economists and game theorists to label some kinds of irrational behaviour from supposedly rational agents. The idea is that rational agents (e.g. humans) don't have time/effort/inclination to calculate the correct rational response in a given situation, so there is a bound on the agents' rationality which does not allow the agent to complete the calculation, and may lead them to behave irrationally.

In understanding how we describe claims ruling, it is useful to think that some normal plays (including careless or inferior) could be classed as boundedly rational while remaining strictly irrational. I don't know whether this concept would help in interpreting "irrational" in Law 70E1.