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How to detect cheaters at Poker and other card games?

How to detect cheaters at Poker and other card games?

Just because you are dealing, doesn't mean you can't be cheated at poker or any card game. When money is involved, there will always be someone who will be ready to exploit you or your friends. The best cheaters are always the ones you least expect, and often will handle the cards sloppily to throw you off guard.

There are countless ways to cheat, but the ones we will discuss here are the most common you would come across in a private card game. For more advanced cheating techniques, check out our article on casino protection.

Advantage play, marked cards, and sleight of hand are the three main ways you can be swindled. With each having their advantages and disadvantages.

Advantage play is not strictly cheating, as you are looking for errors in opponents game-play. Nonetheless you should be weary of this in private games. Everyone deals and shuffles the cards differently. If you look closely when the dealer shuffles, most untrained individuals will leave a bed of cards on the top or bottom of the deck. If you remember those cards from either the discard pile or the last hand gathered, you have a huge advantage over your opponents. If the cards are cut, glance and remember approximately where, and sometimes they will start to come out on the flop, leaving you knowing the turn and river. Additionally, some people will flash the bottom card of the deck inadvertently, and knowing that card will NOT be dealt is a huge advantage that will magnify over time. Occasionally you can see flashes of cards as they are dealt as well, especially if you are seated to the left from the dealer's perspective  (first base) as this gives you a good angle. If you remember these you will be many steps ahead of your opponents. Conversely, if you are dealing, practice good shuffling and dealing technique to help prevent others from shuffle tracking and peeking while you deal.

Marked cards, 'paper', or 'readers' is what most people think of when people cheat at cards. If you are caught switching in a marked deck, or providing one at a game, you would be in a world of trouble. There are entire books written on this, most notably Steve Forte's Gambling Protection series, we will cover the basics. Essentially cards are either printed with, or modified after printing to have identifiable marks on the backs (or faces, surprisingly as well, via small bumps). A rank marked deck will use block-out techniques or scratches to scrape out parts of the design on the card backs so you can identify the playing cards. You can often spot these by holding the entire deck squared in your hands and using your thumb to flick through the cards from the back, if you see some areas of the back design flicker and change, the cards are marked.

Though keep in mind with decks other than Legends, such as Bicycle or Bee branded decks (below), the cutting registration is often extremely mis-aligned, which is why the borders of the cards will often appear different sizes and shift around. 

Cutting Error Bicycle Cards

Legends decks use our signature Diamond Cut process, which allows for much tighter registration, and thinner borders, offering much more protection for casinos and private games. Off-cut cards (see Bicycle playing cards in photo on the right) aren't marked per-say, but one could combine cards from one deck with say, all the aces short bordered on one side, and add them to a deck with better registration for a near factory printed marked deck, and re-seal the cards in a factory printed box. These are called sorts and are quite sophisticated.

Shade is another advanced technique of marking playing cards, largely undetectable with the above method, and used for professionals only as they require difficult training to detect. We printed a deck for magicians named Sharps, which is perhaps the world's first factory printed deck utilizing shade, a fun experiment in modern print technology and a highly saught-after deck.

Another form of paper scams are marking the cards while playing, either with bends or waves in the cards, or nail nicks in the edge. One cheater was rumored to eat fried chicken at the table and use the grease to mark cards during an evening of gameplay. Always use new, sealed, decks of cards for your games, and change them out frequently, especially if the stakes are high.

Sleight-of-hand is perhaps the most difficult form of cheating, requiring months if not years of practice. The stakes are high for cheaters using sleight of hand, if you get caught, there is rarely an excuse you could use to get out of a situation. Bottom and second dealing are some of the most challenging slights to use while cheating, as you can catch a hanger that doesn't come completely out of the deck. Or you could be caught mucking (switching) cards, which obviously is disastrous. Generally, individuals proficient in sleight of hand cheating will only become experts in 1-2 moves, and use them very sparingly only the stakes are the highest. Additionally, they are often excellent players without cheating, and when they need that edge, they have it. Beware as you will not detect let alone suspect the actions of a sophisticated sleight of hand cheater. You can only suspect based on game play and odds, play cautiously or leave the game if you suspect anybody of sleight-of-hand cheating. Accusing them is also typically a bad idea, as they could be partners with other players, and typically have unsavory friends in their circles.

We still haven't touched on deck-stacking, coolers, splash moves, check copping, and many other forms of cheating with playing cards. If you're interested in more just leave a comment below and we can write another article, or check out some references below. Until then, stay safe and protected in your card games!


A few interesting references;

  1. The 'bible' on casino and poker cheating and protection: Steve Forte's Poker Protection and Gambling Protection series.
  2. A bit outdated, but contains relevant information: Cheating at Hold'em with David Malek 
  3. COLLAPSE - Philosophical Research and Development;
    A transdisciplinary survey of practices that produce, analyse, and exploit risk and uncertainty, the eighth volume of Collapse uncovers the conceptual underpinnings of methods designed to extract value from contingency―at the gaming table, in the markets, and in life. The indictment of “casino capitalism” and the centrality of risk to contemporary society are traced back to a ubiquitous image of thought that originated in games of chance, but which is no longer adequate to address a world whose realities are now shaped by risk models and trading in speculative futures.

    To challenge the “casino” model, this volume brings together philosophers who extend the thinking of contingency beyond statistical modelling, professional traders and gamblers whose lifelong experience has shaped their understanding of chance, researchers analysing the perception and treatment of risk and uncertainty in diverse arenas including derivatives trading, quantum physics, insurance, sonic experimentation, literature, futurology, mathematics, and machine gambling, and artists whose work addresses both the desire to confront chance and the need to tame it by bringing it to order.