Prisoner's Dilemma

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"Just think of it as a game. Whoever talks first is the winner."
Sam Kennedy, Murder by Numbers

A situation arises where two or more characters have two choices: cooperate with each other, or betray each other. Unfortunately for them, although everyone cooperating would be better than everyone betraying, each of them would be better off betraying. This usually leads them to betray en masse leaving everyone worse off, but in some instances they can overcome this and cooperate, usually by trust or commitment.

The classic example is two prisoners (hence the name) who are caught and are being charged with some minor offence that the prosecution can prove. But the prosecution wants them for some other crime for which it has no proof. So an offer is made to each prisoner: if he rats out his partner, no charges will be pressed and he will go free...unless his partner rats him out too. If that happens, both get charged with the bigger crime. If both stay quiet, they both get time for the minor charge; if both talk, they both get time for the bigger charge. Although both cooperating is better than both betraying, it is individually better to betray no matter what your partner does. If you ever get into one of these situations, you'd better hope the other person doesn't have Chronic Backstabbing Disorder.

Note that for cops, a common tactic of Lying to the Perp involves pretending the other guy talked.

The Other Wiki has more information about the subject.

See Mexican Standoff for a more specific example of this trope. Related to Teeth-Clenched Teamwork, We ARE Struggling Together and Inevitable Mutual Betrayal. Possibly related to A House Divided. Contrast Rats in a Box and Power of Trust.


Examples:

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    Comic Books 
  • Discussed in Tom Strong. Tom, attempting to prevent his world from being taken over by super-advanced Aztecs, is captured by them and released by their cyber-god, who asks to be released from his virtual prison in return. Though Tom is wary that the god will continue to take over parallel worlds, he keeps the bargain. The god chooses to quit the Aztec conquest, ruling the worlds that have already been conquered, and explains to Tom why he chose to trust him based on this dilemma.
  • In The Incredible Hercules, both Hercules and his partner Amadeus Cho are captured by the Greek god Hephaestus. The rooms they're trapped in both have a switch which will open the other cell's door and allow escape, but will flood the room of the person who pressed it with a gas that not even Hercules can survive. Once the countdown starts, both Herc and Cho press their buttons instantly, setting each other free.

    Films - Live-Action 
  • In Drive, Nino and the Driver would be better off if the Driver gave the money back and promised never to talk about it, and Nino left him alone. Of course Nino can't trust him, and decides it's better to kill him.
  • The Dark Knight has an explicit but a little more sadistic Prisoner's Dilemma with actual prisoners. In the boat sequence, each boat has a detonator to a bomb on the other boat. If they blow the other boat, their own bomb is disarmed. One prisoner even hints at one of the usual solutions to Prisoner's Dilemmas committing not to blow the other boat by ditching the detonator. Of course this being the Joker, he has a secondary detonator set to blow both boats if they cooperate, which Batman stops him from doing.
  • In The Edukators, when Jan and Julie got caught breaking and entering by Hardenberg in his house, it would be better for all of them if Hardenberg could credibly promise not to tell anyone about it and they chose not to kidnap him.
  • In Murder by Numbers the detectives try to pull a classic Prisoner's Dilemma in the interrogation scene, but the trust between the prisoners and the arrival of the lawyers prevents the defection.
  • In the French film Two Days One Night, the owners of a factory offer the employees a bonus if they agree to fire the protagonist, who happens to be the least productive employee (due to her clinical depression). In the long run, it might be better for the employees to stand together and preserve their collective bargaining power. However, in the short run, many of the employees really need the bonus money, and thus vote almost unanimously to fire the protagonist.

    Live-Action TV 
  • This was an element of gameplay in The Mole. It was better for contestants to work together and give maximum effort in challenges, because that increased the pot that they were playing for. However, since The Mole was sabotaging the game, and players who incorrectly guessed the identity of The Mole faced risk of elimination in the quiz at the end of the episode, contestants would sometimes sabotage challenges in order to draw false suspicion on themselves.
  • The GSN game show Friend or Foe revolves around this trope. After teams of players work together to answer questions to earn money for their trust fund, then go to the trust box to decide how to split the money. If both players choose "Friend," they split the money 50/50. If one chooses "Friend" but the other chooses "Foe," the Foe takes all the money while the Friend leaves with nothing. If both players choose "Foe," they both walk away with nothing.
  • In an episode of The Commish Tony uses the dilemma to trap a couple of killers. He has them brought in and kept for hours without food or drink. He explains the dilemma to one, who won't talk, so Tony lets him go. Then he has the DA go into the other holding room and offer the second guy whatever food he wants. The first guy sees the second guy through the office window, with the DA frantically scribbling down what he's saying, and thinks that the second guy is ratting him out, so the first guy blames the second one for the actual murder.
  • Midsomer Murders: Barnaby uses the trope in one episode to get two individual murderers not to confess, but to witness that they saw the other committing a murder.
  • In the Quantico episode "Cover", FBI Academy Deputy Director Miranda Shaw uses a variant as a Secret Test of Character. After getting her FBI cadets pissed off at each other, she tells them that they are to vote for three candidates to be cut from the training program. Refuse to vote, and she cuts ten. Alex tries to get her classmates to abstain, but Simon chickens out. Truth is, Miranda wasn't planning to cut anyone: the correct response was to stick with each other regardless of personal feelings, and she gives Simon and the candidates about to follow his lead a What the Hell, Hero? speech and threatens him with expulsion if he makes another mistake like that.
  • The Castle episode "The Double Down" unusually presents the dilemma from the interrogators' perspective. The team realizes that two seemingly unconnected murders were prearranged to be done by the person who had motive for the other murder, in order to provide airtight alibis for the one they would be suspected of. Unfortunately they don't have any hard evidence, so if both suspects keep mum they can't prove the theory. To solve it, Ryan and Esposito tell the weaker link while Castle and Beckett are interrogating him that his partner has already given him up to save his own skin, which convinces the bluffed suspect to confess.
  • This was frequently invoked on Jeopardy! in situations where there is a tie for first place going into the Final Jeopardy! round. The two tied contestants have no choice but to bet either All or Nothing on the Final Jeopardy! clue, depending on how much they trust the other to bet $0. In the best-case scenario, both bet $0 and are declared co-champions regardless of whether they get Final Jeopardy! right or wrong; worst-case scenario is that they both zero out on an incorrect response and the third contestant wins (unless they too bet everything). However, since ties for first place (and hence the co-champion rule) were abolished at the start of Season 31, this can no longer be done without leading to a Tiebreaker clue.

    Video Games 
  • A variant of the game appears in The Talos Principle's expansion Road to Gehenna on the message board that you explore within the game world. This version is meant as a combination game and social experiment, and has somewhat unconventional rules: if both participants "betray", each earns two points. If both "co-operate", neither person earns any points. If one betrays and the other co-operates, the former receives one point and the latter three points. Whoever has the most points at the end of the round loses. In contrast to the original dilemma, the participants are able to communicate beforehand, making the game more about bluffing than principles. Because of the way the points are awarded, the only way to win is to convince the opponent to co-operate while you betray (after which point, both parties will sensibly betray until the game ends).
  • In Knights of the Old Republic, a computer trying to determine if the Player Character is authorized to access it proposes a Prisoner's Dilemma scenario and asks the PC what they would do. In this case, betraying their companion is the "right" choice because it works out better for you no matter what the companion does, but the PC can reject the computer's moral vision and still gain access.
  • One of the games in The Jackbox Party Pack 3, Trivia Murder Party, has a minigame based on this scenario called "Decisions, Decisions". The host leaves a pile of money for the people in the game to take. If at least one person takes the money, anyone who didn't take it dies. If everyone takes the money, everyone dies. The only scenario where everyone is kept alive is if absolutely nobody takes any money, but would you really trust your friends to cooperate with you, especially if it involves more than 2 people?

    Visual Novels 
  • This is the basis behind the Nonary Game: Ambidex Edition in Zero Escape: Virtue's Last Reward, and Phi spends about 3 minutes explaining the concept to Sigma. The object is to escape the facility with 9 Bracelet Points, and the only way to get BP is to vote at the end of each round either for or against the people whom you cleared the round with. If both sides vote "ally," then both gain 2 BP; if one side votes "betray" while the other votes "ally," then the betraying side gains 3 BP and the betrayed loses 2. If both decide to betray, then neither will gain any BP for that round (which becomes a problem since the door to escape can only open once, meaning someone who played smarter could reach 9 BP before you do). Failing to vote causes the system to automatically vote "ally" on your behalf, which would seem to be an easy solution — but both sides failing to vote results in death by lethal injection via the point-counting bracelets worn by the players (which also happens to be the punishment for dropping to 0 BP). Funnily enough, after finishing her explanation, Sigma concludes that they should vote to ally, and Phi instead insists on betraying Luna.
  • In Danganronpa, Celestia Ludenberg references the concept and uses the example of two countries building their military strength under fear of betrayal from the other to explain the School Life of Mutual Killing that the 15 students have been forced into (in which uniting together against The Mastermind would be ideal, but none can escape the possibility of someone cracking under the pressure of wanting to escape the school by choosing to kill someone else).

    Web Comics 

    Web Original 

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