In most formats partners play as a team of two (or as part of a team of four or six) and are not mixed. Cheating at bridge has some interesting information the

In most formats partners play as a team of two (or as part of a team of four or six) and are not mixed. Cheating at bridge has some interesting information theory elements. Communication between partners is explicitly allowed during the bidding phase of bridge via bids (e.g. a bid of "2 clubs" may imply a lot about the cards the bidder holds) but must follow a convention which is known to your opponents (so they learn just as much from that bid as your partner does). Communication during the playing phase of bridge is explicitly forbidden, e.g. you are not supposed to take a long time making a decision about which card to play, from which your partner could infer which cards you are probably choosing between. Most cheating schemes occur between the two phases, after the bidding but before the play starts where the defenders try to tell each other some critical feature(s) of their hands (e.g. that they hold the queen of trumps). Because a tiny amount of data can make a difference (a single bit could communicate the above fact) cheating strategies come in many forms. Making a noise (e.g. coughing or tapping) were classics, but can be overheard and may be obvious in review. The position of a body part, the choice of which hand to touch something with, the angle that a pencil or the bidding tray are placed at can all communicate information. If you want to see some analysis of a relatively recent cheating scandal (and some of the anti-cheat devices that are used at top tournaments) YouTube has a few videos on the Israeli pair Fisher & Schwartz: https://www.youtube.com/watch?v=831tJ4EHLBY https://www.youtube.com/watch?v=831tJ4EHLBY