Cards Exposed Before Play
65. If, after the cards have been dealt, and before the trump
declaration has been finally determined, any player lead or expose a
card, the partner of the offending player may not make any further bid
or double during that hand, and the card is subject to call. When the
partner of the offending player is the original leader, the declarer
may prohibit the suit of the exposed card being the initial lead.
66. If, after the final declaration has been made and before a card is
led, the partner of the leader to the first trick expose a card, the
declarer may, in addition to calling the card, prohibit the lead of the
suit of the exposed card; should the rightful leader expose a card it
is subject to call.
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