That's the proposition of David Davies MP, who is this week's Cornerstone blogger and an occasional police constable.
In a robust response to "the bleeding heart brigade", he argues that investing another £3bn on prison places could reap at least ten times that amount in revenue as a result of fewer crimes being committed:
"Another government report states that most crime is committed by a hard core of 100,000 criminals, of whom only 15,000 are in prison at any one time. Removing these career criminals would double the prison population and therefore double the cost of prison spending from the current spending level of £3billion to £6billion each year. However, by the Government’s own estimate, in return for this £3billion outlay we could expect crime rates to be halved saving the country between £30-£45 billion."