The Laws of Duplicate Bridge 7

Law 21
Misinformation
A. Call or Play Based on Players Own Misunderstanding
No rectification or redress is due to a player who acts on the basis of his/her own understanding.
B. Call Based on Misinformation From and Opponent
1. a) Until the end of the auction period (see Law 17D) and provided that his partner has not subsequently called, a player may change a call without other rectification for his/her side when the Director judges that the decision to make the call could well have been influenced by misinformation given to the player by an opponent. Failure to alert promptly where an alert is required by the Regulating Authority is deemed misinformation.
b) The Director is to presume Mistaken Explanation rather than Mistaken Call in the absence of evidence to the contrary.
2. When a player elects to change a call because of misinformation (as in 1 preceding) his/her LHO may then in turn change any subsequent call he/she has made, but Law 16C applies.
3. When it is too late to change a call and the Director judges that the offending side gained an advantage from the irregularity he/she awards an adjusted score.
Law 22
End of Auction
The auction ends when:
A. one or more players having bid, there are three consecutive passes in rotation subsequent to the last bid. The last bid becomes the contract (but see Law 19D).
B. all 4 players pass (but see Law 25). The hands are returned to the board without play. There shall not be a re-deal.
Law 23
Comparable Call
A. Definition
A call that replaces a withdrawn call is a comparable call, if it:
1. Has the same or similar meaning as that attributable to the withdrawn call, or;
2. Defines a subset of the possible meanings attributable to the withdrawn call, or;
3. Has the same purpose (e.g. an asking bid or relay) as that attributable to the withdrawn call.
B. No Rectification
When a call is cancelled (as per Law 29B) and the offender chooses at his/her proper turn to replace the irregularity with a proper call, then both the auction and play continue without further clarification. Law 16C2 does not apply, but see C following.
C. Non-offending Side Damaged
If following the substitution of a comparable call (see Laws 27B1(b), 30B1(b)(i), 31A2(a) and 32A2(a)) the Director judges at the end of the play that without the assistance gained through the infraction the outcome of the board could well have been different, and in consequence the non-offending side is damaged, he/she shall award an adjusted score. (See Law 12C1 (b)).
Law 24
Card Exposed or Led During the Auction
When the Director determines that during the auction, because of a player’s own error, one or more cards of that player’s hand were in a position for the face to be seen by his/her partner, the Director shall require that every such card be placed face up on the table until the auction ends. Information from cards thus exposed is authorised for the non-offending side but unauthorised for the offending side (see Law 16C).
A. Low Card Not Prematurely Led
If it is a single card below the rank of an honour and not prematurely led, there is no further rectification (but see E following).
B. Single Card of Honour Rank or Card Prematurely Led
If it is a single card of honour rank or is any card prematurely led, offender’s partner must pass on their next turn to call (see Law 72C when a pass damages the non-offending side).
C. Two or More Cards Are Exposed
If two or more cards are so exposed offender’s partner must pass at their next turn to call (see Law 72C when a pass damages the non-offending side).
D. Declaring Side
If the offender becomes declarer or dummy the cards are picked up and returned to the hand.
E. Defenders
If at the conclusion of the auction the offender is to become a defender, every such card becomes a penalty card (see Laws 50 and 51).

Law 25
Legal and Illegal Changes of Call
A. Unintended Call
1. If a player discovers that they have not made the call they intended to make, they may, until their partner makes a call, substitute the call they intended for the unintended call. The second (intended) call stands and is subject to the appropriate Law, but the lead restrictions in Law 26 do not apply.
2. If the player’s original intent was to make the call selected or voiced, that call stands. A change of call may be allowed because of a mechanical error or a slip of the tongue, but not because of a loss of concentration regarding the intent of the action.
3. A player is allowed to replace an unintended call if the conditions described in A1 above are met, no matter how he/she may become aware of their error.
4. No substitution of call may be made when his/her partner has made a subsequent call.
5. If the auction ends before it reached the players partner no substitution may occur after the end of the auction period (see Law 17D).
6. If a substitution is allowed the LHO may withdraw any call they made over the first call.. Information from the withdrawn call is authorised to his/her side and unauthorised to the opponents.
B. Call Intended
1. A substituted call not permitted by A may be accepted by the offender’s LHO. (It is accepted if LHO calls intentionally over it). The first call is then withdrawn, the second call stands and the auction continues (Law 26 may apply).
2. Except as in B1, a substitution not permitted by A is cancelled. The original call stands and the auction continues. (Law 26 may apply).
3. Law 16C applies to any call withdrawn or cancelled.
Law 26
Call Withdrawn, Lead Restrictions
A. No Lead Restrictions
When an offending player’s call is withdrawn and it is replaced by a comparable call (see Law 23A) then if he/she becomes a defender there are no lead restrictions for his/her side. Law 16C does not apply, but see Law 23C.
B. Lead Restrictions
When an offending players call is withdrawn and it is not replaced by a comparable call, then if he/she becomes a defender declarer may, at the offender’s partner’s first turn to lead (which may be the opening lead), prohibit offender’s partner from leading any (one) suit which has not been specified in the legal auction by the offender. Such prohibition continues for as long as the offender’s partner retains the lead.