When you don't have enough information to know whether to alert

A bidding sequence I came across recently:

(2C!), P, (2D), X

The opponents opened 2C, alerted; when I asked I was given a typical "strong, artificial, forcing" description (with enough detail that there were no issues with disclosure at that point in the auction). I passed. Responder bid 2D, not alerted. My partner doubled. Should I alert?

I decided to follow the "if in doubt, alert" principle and alerted the bid as "it depends on what 2D means, but I don't think it's takeout" (on the basis that my lack of alert would presumably have informed the opponents that it was takeout). My partnership agreement in this situation was uncertain: SAF 2C followed by natural 2D had never come up before, so there was no relevant partnership experience, and our general principle for undiscussed situations was "if a double can reasonably be takeout, it is". I guess that means the double was in fact systemically takeout (I can't think of any other reasonable meaning for it!), the opposite of what I said! That said, I thought it was highly likely that my partner had missed the lack of alert, so I alerted the opponents to the likely meaning of the double even though it was the opposite of what our agreement said.

Some questions:

• Should I have explained the double as I did, or should it have been explained some other way?
• Is the sequence 2C! (SAF), (P), 2D (not alerted) ever possible, or should 2D always be alerted on the basis that any meaning that actually shows diamonds is highly unexpected?
• Suppose the bidding instead goes (2C!), P, (2D!), X (with an alert on 2D). Partner doesn't ask what 2D means. I thus have UI that partner thinks that 2D is purely artificial:

• Should I therefore take the countersuggested action, and bid as though X is takeout?
• Does the answer to the previous question depend on whether or not 2D! actually shows diamonds? (A meaning like "exactly 6 diamonds" would be both alertable and natural, thus it's possible for the double to be systemically takeout in the absence of UI.)

As usual, I have the feeling that there's something wrong with the alerting regulations here. I guess the last question above could be resolved if system cards were exchanged more commonly at all levels of bridge (I wouldn't have the UI that my partner is guessing what 2D means rather than bidding with knowledge of the meaning if there were a reasonable chance that my partner could have read the opponents' system card).

For what it's worth, although most of the questions above could be resolved simply by making a waiting or "nothing special to show" 2D response to SAF 2C nonalertable, I don't think that's the correct solution, as the principle of "alert all non-natural bids" is a very effective way to make the alerting regulations easier to remember. However, alerting a bid that is non-natural but expected has the issue that it rather undermines the main purpose of alerts: if a player is expecting an alert, it means that they normally won't ask, and then their partnership ends up in trouble if the alert turns out to have some unexpected meaning that completely changes the meaning of their own calls. Perhaps we need a separate sort of alert for non-natural calls, and for unexpected calls?

• BB 2 A 2 These regulations are secondary to the duty of full disclosure (Law 40A). If a player is uncertain
whether the regulations require an alert, but believes it would help the opponents, he should
alert. At the end of the auction the declaring side may offer additional information, even if not
requested. In particular, they are encouraged to draw attention to any calls whose meaning the

2 A 3 It is expected that experienced players will protect themselves in obvious misinformation cases.
If they receive an implausible explanation, and can protect themselves by seeking further
clarification without putting their side’s interests at risk (e.g. by transmitting unauthorised
information or alerting the opposition), failure to do so may prejudice their right to redress.

2 D 2 Unless a player knows that his partner’s call is not alertable (or announceable) he must alert. If
the player is unsure when asked for its meaning he may refer the opponents to the system card
if it is shown there. If there is no relevant partnership understanding, he must not say how he

4 A 6 If there is no alert and no announcement, opponents can assume that there is an understanding
(explicit or implicit) for the meaning of the call that does not require one. See also 2D2

So you should alert and if asked you should give the two possibilities - presumably if 2D is natural then it's takeout, if artificial then it shows diamonds.

If you are not asked about the alert, you should ask yourself when it is your turn to call. Remember that partner's failure to ask about 2D is UI to you, so you will need to continue on the assumption that partner's double related to the agreed meaning of 2D..

I don't think a 2D natural response to an artificial 2C is alertable andy more than a 2D natural response to 1NT is.

• When LHO makes an alerted suit bid and my partner doubles, without asking, I don't know what the double means - because I don't know whether the alerted bid was a natural suit or not.
But then I don't know if my partner knows either. She may have made an assumption about the bid, or not noticed the alert.
So I feel that alerting the double or asking at my turn about LHO bid are both giving UI to my partner.
So I keep quiet and assume that the double is takeout even if it probably isn't.
(With something obvious like an opening 2C I would assume the generally accepted meaning.)

Alan

• @16248 said:
So I feel that alerting the double or asking at my turn about LHO bid are both giving UI to my partner.
So I keep quiet and assume that the double is takeout even if it probably isn't.

You have an obligation in the laws to give your opponents the correct information. You do not have such an obligation to avoid giving UI, though it may limit your partner's options if you do. Note that your partner has already given you UI by failing to ask about the alerted bid before doubling.

• Let's assume:
1. that your agreed system is that a double of a natural 2D would be for take-out; and of an artificial 2D it would be showing a diamond suit.
2. that the opposition's agreement is in fact that 2D is artificial, even though they failed to alert it.

It follows that your actual agreement for the double is that it shows diamonds.
It matters not that the opponents failed to alert it; it matters not whether your partner asked about the meaning of the double; it matters not that your partner might even have got it wrong. None of these change the basic fact of what was your agreed meaning.
If you are asked what the double means, than you have to give an answer of what your agreement is, not what you think partner might have thought he was showing. If you need to find out first what the 2D meant, in order to give correct information, then you must ask. Your obligation (as Gordon says) is to give correct information.

Well, based on the assumptions above, the double shouldn't be alerted, even if 2D was artificial. So there is no requirement (IMO) to alert.
However, if you had some alternative artificial meaning for the double of an artificial 2D (such as being part of a system of 2-suited overcalls of artificial strong openings), then the double is alertable. In that situation I would alert. if they ask what the double means then you should enquire about the 2D meaning.
Blue Book 4A5 was probably intended to cover a slightly different scenario, but it seems to me to be quite relevant to this one:
Even if a player cannot explain the meaning of partner’s call, they should still alert (or announce)
it if they believe that it may be required.

• Playing devil's advocate for a moment, and remembering that it is the system that opponents are entitled to know about, not what the actual call means.

Under 4 A 6 If there is no alert and no announcement, opponents can assume that there is an understanding
(explicit or implicit) for the meaning of the call that does not require one.
Thus you can (and for the purposes of alerting should) assume the 2D is natural. This means the double is not alertable, as under the system it is takeout, irrespective of the fact that it probably isn't.

_2 A 3 It is expected that experienced players will protect themselves in obvious misinformation cases. _ This does not say that you are obliged to protect your opponents if they give misinformation. So you can't come back later and claim redress because it wasn't a natural diamond bid, but you don't have to (and shouldn't) make assumptions about opponents bidding when it comes to alerting.

• @JeremyChild said:
...This does not say that you are obliged to protect your opponents if they give misinformation.

Are you suggesting that, if the opponents forget to alert a call, it's OK to knowingly misinform them about your own system?

• They say that they forgot to alert, I say that they gave misinformation, which caused us to misinterpret our own bids.

• It is still misinformation if you give an explanation that doesn't match your partnership agreement, even if the reasons you have for doing so are entirely innocent. The opponents are still entitled to a correct explanation, whatever other infractions they might have committed.
The only difference this might make is that, if it comes to having to make an adjustment because the oppo have been misinformed, you might regard them as no longer being the non-offending side.

• @Mitch said:

@JeremyChild said:
...This does not say that you are obliged to protect your opponents if they give misinformation.

Are you suggesting that, if the opponents forget to alert a call, it's OK to knowingly misinform them about your own system?

No. I'm saying that if opponents do not alert a call, that call is deemed natural and the partnership agreement over what any subsequent call means is affected accordingly.

I may (at my own risk) assume the call should have been alerted, but that's my choice and not the partnership agreement. I can of course always ask.

We're not necessarily talking about an "obvious" situation like 2D (unalerted) after 2C (alerted). Suppose it goes
W N E S
I suspect from my hand (which has 6 Spades) that 2S is not natural, but it could be. It is not alerted so my double would mean takeout as that is what our system is.

• @JeremyChild said:

We're not necessarily talking about an "obvious" situation like 2D (unalerted) after 2C (alerted). Suppose it goes
W N E S