>>>Since, according to the premise, the mayor should know about at least 39 of the 40 unfaithful wives - and the other townsmen know that he knows - he will get into trouble for his understatement.
>>
>>Well, there is the taboo. It doesn't say that they can't say anything. Maybe the mayor decides to take unilateral action and be diplomatic about things at the same time.
>>
>>Unless his wife is also unfaithful, he should know exactly how many women will be shot and when.
>
>I don't understand why anyone will be shot, if the mayor said something which everybody knew anyway. What new information is he giving?

Allright say there is 1 unfaithful wife.
What will happen?

Remember the man knows about every unfaithful wife except his own.
And because of the taboo, noone would have told him anything until now.

Remember, you can clean from what the Mayor said that there must be at least 1 unfaithful wife.