Posted 2015-April-30, 00:48
73D2 : 2. A player may not attempt to mislead an opponent by means of remark
or gesture, by the haste or hesitancy of a call or play (as in hesitating
before playing a singleton), the manner in which a call or play is made
or by any purposeful deviation from correct procedure.
BUT
73F When a violation of the Proprieties described in this law results in damage
to an innocent opponent, if the Director determines that an innocent player
has drawn a false inference from a remark, manner, tempo, or the like, of an
opponent who has no demonstrable bridge reason for the action, and who
could have known, at the time of the action, that the action could work to
his benefit, the Director shall award an adjusted score (see Law 12C).
North has to decide whether to reject the lead from the wrong hand. This is a demonstrable bridge reason for the pause.
And (for completeness) don't forget law 55C (which deals in cases for example when declarer leads from dummy by 'mistake' when dummy has no obvious entry to find out if RHO objects).
C. Declarer Might Obtain Information
When declarer adopts a line of play that could have been based on
information obtained through the infraction, the Director may award an
adjusted score.
No matter how well you know the laws, there is always something that you'll forget. That is why we have a book.
Get the facts. No matter what people say, get the facts from both sides BEFORE you make a ruling or leave the table.
Remember - just because a TD is called for one possible infraction, it does not mean that there are no others.
In a judgement case - always refer to other TDs and discuss the situation until they agree your decision is correct.
The hardest rulings are inevitably as a result of failure of being called at the correct time. ALWAYS penalize both sides if this happens.