Here is a nice table directly taken from Wikipedia:
Prisoner B Stays Silent | Prisoner B Betrays | |
---|---|---|
Prisoner A Stays Silent | Each serves six months | Prisoner A serves ten years Prisoner B goes free |
Prisoner A Betrays | Prisoner A goes free Prisoner B serves ten years | Each serves five years |
From a game theory standpoint, even though it is in the prisoners best interest to not talk to the police, the risk of the harsh sentence entices both prisoners to betray each other.
So, why the heck bring it up now? Well, I think we're seeing this play out right now with the Michael Vick investigation. For those not up on their NFL scandals, Vick has been indicted on charges related to running a dog fighting ring. The really interesting part is that a few of his cohorts were also indicted. One of them already plead guilty a few weeks ago. This started the pressure on the other three, including Vick. Now there has been an announcement that Vick's two other buddies are scheduled to enter pleas later this week. Uh-oh.
If you look at the table above, that could put all of them squarely (or, more precisely, rectangularly) in the lower right box. Granted, I am sort of forcing this analogy a bit especially since there is likely a boatload of evidence coaxing these confessions, but it is still fascinating to watch from a game theoretic standpoint. It is also fascinating to watch in terms of hoping dog torturers get their comeuppances.