Screen (bridge)

A screen is a device used in some tournaments in duplicate bridge that visually separates partners at the table from each other, in order to reduce the exchange of unauthorized information and prevent some forms of cheating. It is a panel made of plywood, spanned canvas or similar material, which is placed vertically, diagonally across the playing table, with a small door in the center and a slit beneath it. The door is closed during the bidding stage, and the players place their calls using bidding cards on a movable tray, which slides under the door. After the opening lead, the door is opened, but its size allows the players only to see the hands and cards played from the opposite side of the screen, not their partner's face.

Screens are normally used on high-level competitions, such as World Bridge Olympiads, national teams championships and similar. They are always accompanied with bidding boxes and a tray for moving the bids across. Screens were first introduced in Bermuda Bowl competition in 1975, at the home venue in Bermuda; however, they didn't prevent the foot-tapping scandal involving two Italian players. Following that event, screens used in high-level events extend under the table to the floor forming a barrier running diagonally between two table legs.

Laws of Duplicate Contract Bridge state that "Players are authorized to base their calls and plays on information from legal calls and plays and from mannerisms of opponents. To base a call or play on other extraneous information may be an infraction of law.". Also, "After a player makes available to his partner extraneous information that may suggest a call or play, as by means of a remark, a question, a reply to a question, or by unmistakable hesitation, unwonted speed, special emphasis, tone, gesture, movement, mannerism or the like, the partner may not choose from among logical alternative actions one that could demonstrably have been suggested over another by the extraneous information." In other words, if a player receives such an unauthorized information from the partner (hesitation being the most frequent source), he may not act according to its (perceived) consequences (provided it is not an obvious thing to do, but "obvious" has rather high standard according to the laws).

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Wikipedia