Cops are probably already using dirty tricks like lying to get people to confess, such as "You might as well confess right away, your partner in the next room have already described what happened" ( or maybe IŽve seen too many movies
)
If we would allow torture ( in this case we donŽt know if the cops were serious about the threat) what would happen if the torture-victim was innocent. "Oh sorry there buddy, eh... IŽll...oh let me help you find all your teeth...there you are, I believe that was all of them."
It is true though that torture is a very effective method that are still used in some countries.
On the other hand a guy being tortured would admitt to anything sooner or later.