Punishment can be an extremely effective method of teaching but only if certain conditions are met. Meeting these conditions is often impossible or is so challenging that it is easier to take a different approach. First and foremost, punishment must not be used as retribution. Punishment is a learning tool, not a means for revenge. That’s why Ted Turner’s classification of death as punishment is incorrect: dead things don’t learn. Punishment must be initially severe, must fit the crime, must be consistent, immediate, and not reliably associated with inconvenient [predictors], such as a particular person.
Ideally, an appropriate alternative behavior is available. My all-time favorite example of the perfect punishment comes from Karen Pryor, in her book Don’t Shoot the Dog!. She imagines what the world would be like if every time someone parked a car illegally, the car exploded. I suspect no one would ever park illegally! This punishment completely fits the bill: it is intense, it is immediate, it happens every time, it happens remotely, and it fits the crime because your car no longer exists. Contrast this with the way things usually happen: I receive a ticket that doesn’t have to be paid for a week or two, the fine is not heavy ($20 in Toronto), more often than not, I get away with it (I would guess I am on a FR-20 to FR-30 schedule of punishment), and if I watch for the parking enforcement officer coming down the street, I move my car and avoid a ticket. It’s not a totally stupid system, though - towing is an effective punisher - I have never parked in a tow-away zone since the first and only time I came back to find my car gone :-(!