*4♦ was prefaced by a STOP card, at which point the TD was called.
I ruled that North had bid 4♦ so that call would stand, but that South should take care not to take any advantage of any unauthorized information conveyed by the showing of the STOP card. EW could draw any conclusions they liked, but at their own risk. I invited the players to call me back if they felt they might have been damaged by the irregularity.
South decided that his most ethical action was to pass 4♦, which became the final contract and went one off. South called me back and said that if his partner had not placed the STOP card he would have bid 5♦, which East contended he would have doubled. North claimed she would have removed this to 6♣.
Is there any grounds for adjusting the score?
.P..1♦..P..2♣
.P..2♠..P..3♥(A)
.P..4♦*