Join Bridge Winners
The Elements of an Implicit Understanding

As a partnership evolves, partners will usually discuss more bidding sequences and possible refinements of conventions. However, there is another aspect of the partnership that necessarily remains unspoken, the implicit understanding. Once you discuss a sequence or convention, your understanding is no longer implicit. I’d like to try to identify the moment at which a director can determine that one partner’s tendencies or style has become an implicit partnership understanding.

The Laws

The Laws of Duplicate Bridge require disclosure upon an opponent’s inquiry of not only a partnership’s explicit agreements, but also “implicit understandings.”

“Whether explicit or implicit, an agreement between partners is a partnership understanding.” (Law 40B1(b)) “Partnership understandings as to the methods adopted by a partnership may be reached explicitly in discussion or implicitly through mutual experience or awareness of the players.” (Law 40A1(a)) “A player may deviate from his side’s announced understandings always, provided that his partner has no more reason to be aware of the deviation than have the opponents. Repeated deviations lead to implicit understandings, which then form part of the partnership’s methods and must be disclosed in accordance with the regulations governing disclosure of system.” (Law 40C1)


While the words “understanding” and “agreement” are often used interchangeably, including in the above Laws, I’ll use “understanding” as the more inclusive term, because while all agreements are understandings, not all understandings are agreements.

To illustrate, in your experience it’s much easier to compete when partner’s two-suited overcall promises at least five cards in each of the two suits. However, you have an aggressive partner who is aware that hands with five-four distribution are much more common than five-five distribution, and you begin to notice that partner has been experimenting with two-suited overcalls including five-four hands. You don’t do it yourself and you don’t agree with these experiments, but you are beginning to understand partner’s shape might be five-four. Sometimes your observations of this repeated conduct will give rise to an implicit understanding before you deem it appropriate to have a conversation about the minimum requirements for two-suited overcalls and reach an express understanding.

Is actual, subjective awareness essential to an implicit understanding?

Law 40A1(a) refers to a partner’s “awareness.” Let’s discuss the consequences of grounding an implicit understanding on a partner’s subjective awareness by considering two types of partners, one (a BW regular) who is particularly observant and another (let’s call him “the client”) who is preoccupied with his own participation in the game and isn't paying as close attention to his partner (let’s call her “the pro”).

Like all regular BW readers, you are unusually observant at the bridge table. You begin a partnership with someone (“NP”) after having plenty of experience playing against NP. When you and NP first put together a convention card, you agreed to some conventional two-suited calls, but may not have had the time or inclination to discuss expected shape. Would it be fair to say you have an implicit understanding based on your mutual pre-partnership table experience, or is an implicit understanding limited to what you observe your new partner doing as your partner? I think mutual experience as opponents, if any, is relevant.

In stark contrast is the client. During the auction and the play, the client may be preoccupied with remembering conventions, playing in tempo, counting his own high card points and suit distribution in other hands, observing the pro’s table presence, and may not have noticed that the pro has often opened or overcalled 1NT with a 14 count, despite their agreement that it shows a minimum of 15 HCP.

Should this client's willful or woeful ignorance forever immunize this partnership against an implicit understanding arising? Of course, the client can’t disclose what he truly doesn’t know, but an alert opponent should be able to make the client aware of the pro’s style or tendencies. It may take a director call or two or maybe just a quiet comment after a hand, “you only had a 14-count.” If willful ignorance is allowed to be an excuse, nothing will prevent this partnership from continuing to mislead other less alert opponents about their secret understanding because it remains a secret to the client.

I assert that a director is not required to accept the client’s statement, “I've never noticed that she opened 1NT with fewer than 15 HCP.” If it has happened often enough that a reasonably observant partner should have noticed, and the opponents have a strong suspicion what is going on, then a director should be able to determine an implied understanding exists despite the client’s true ignorance, and the consequences of nondisclosure attach.  (Laws 40B4, 40B6(b), 40C1

Is there an objective formula for establishing an implicit understanding?

Law 40C1 points in the direction of an objective formula by stating, “Repeated deviations lead to implicit understandings.” Returning to the strong NT opening example, if the pro opens every flat 14 1NT, at some point in time the client better start announcing “14 to 17.” But after how many deviations from their express agreement?

Presumably the first deviation is free and doesn’t alter the partnership’s express agreement. Is there a minimum ratio or frequency after which a deviation establishes an implicit understanding? Can it sensibly be quantified? Surely if the pro opens over half her 14 counts 1NT, it becomes at least an implicit agreement, but is there a frequency under 50% that qualifies as a substantial or significant proportion of the time? One time in three may not establish a pattern, but how about 2 in 6, 3 in 9, 10 times in 30, or 33 times out of 100?

 If you agree that a percentage is the key element, keep in mind that a director who adopts a rule of thumb, for example, that deviations of one in three amount to an implicit understanding may have a hard time applying the rule to an unfamiliar partnership. Sure the director call was prompted by a deviation, but how is the director to know if it’s happened before? Presumably the partners will answer honestly if the director asks about their history.  But what if their recollection disagrees with that of the opponents who called the director?  

In contrast to the unfamiliar director is the director who, based on the director’s experience as your partner or opponent, may be more aware of your tendencies than your new partner. Let’s say in a weak NT context you’ve responded to a minor opening with a three-card major 8% of the time to avoid wrongsiding the contract. Opponents call this familiar director when your three-card major appears in dummy. Should the director be able to instruct your new partner that he now has an implicit understanding based on the director’s experience with your tendencies?

Is the dramatic nature of the deviation relevant?

Is the answer to establishing an implicit understanding strictly a numbers game, or can it depend on how dramatic the deviation is? What I mean by "dramatic" in this context is a deviation that calls attention to itself.

Let’s say the client has insisted that the pro play two over one, but the pro nevertheless passes after announcing the client’s 1NT response to a major opening as “forcing.” It turns out to be the only makeable contract and the client notices at the dinner break that they won the board in a team event. In the second session of play on the same day, it happens again. The pro announces “forcing” and passes. Is this deviation from their agreement so dramatic that the pro should start announcing “semi-forcing” after passing twice in the same day?  Has an implicit understanding arisen?

What do you think?

I wish I could propose an all-purpose test or formula that would be readily acceptable as identifying the threshold for when one partner’s tendencies or style becomes an implicit understanding, but I'm afraid I've just demonstrated why the Laws have not attempted to provide more than general guidelines. Maybe there are other factors I’ve overlooked (there usually are). What do you think? I don’t expect every option to get a vote, but I’m trying to be comprehensive.

1. (Factor #1) The only essential element of an implicit understanding is partner's subjective awareness of deviations from an express agreement.
2. (Factor #2) The test for an implicit understanding must be objective, based solely on deviations being sufficiently frequent that a reasonably observant partner should have noticed.
3. (Factor #3) The dramatic nature of the deviations is the only essential element of an implicit understanding. Frequency is irrelevant if they are dramatic enough.
4. A director should consider all three of the above factors in determining the existence of an implicit understanding, with no one being necessarily decisive.
5. Partner's subjective awareness (#1) is unnecessary to an implicit understanding, while the frequency (#2) and dramatic nature (#3) of the deviations are critical.
6. No minimum frequency of deviations (#2) is necessary if they have been dramatic enough (#3) to prompt partner's subjective awareness (#1).
7. The dramatic nature of the deviations (#3) is irrelevant if the deviations have been so frequent (#2) as to prompt partner's subjective awareness (#1).
8. There are other factors relevant to establishing an implicit understanding that you’ve overlooked. (Please explain.)
9. The only essential elements of an implicit understanding are that it is an "understanding" that is "implicit." Don't overanalyze it.

Sorry, to answer polls. Registered users can vote in polls, and can also browse other users' public votes! and participate in the discussion.

Getting results...
Getting Comments... loading...

Bottom Home Top