One of the reasons why our prisons are full to bursting is because our sentencing regime is punitive, more punitive than most European countries.  Backbenchers are proposing a new punitive measure on knife crime, which will both increase prison numbers and be ineffective in reducing knife crime.  It is a tangled political tale, but the papers indicate that the Lord Chancellor wanted to introduce a new sanction for knife crime – mandatory imprisonment for knife crime on the second offence for children or adults.  This can include straight possession.  I am no supporter of knife possession, or knife crime, but I also know that imprisonment particularly for children (under 18 year olds) is not the answer.  Short prison sentences are expensive and in effective – over two thirds of children released from custody are re-convicted within a year.   There is no evidence whatsoever that imprisonment acts as a deterrent to those who carry or use knives.  This doesn’t mean that serious crimes involving a knife should not be prosecuted.  But it does mean that mandatory imprisonment for a teenager who has twice been found with a knife in his pocket is bad policy, and totally fetters the discretion of judges.  Its the politics of this that are depressing. Reports say the LibDems were resisting the move, when sources close to the Lord Chancellor leaked it.  Then, a backbencher put forward their own amendment (presumably tacitly backed by the Lord Chancellor), which Labour are seriously considering supporting.   This plunges us back to the arms race in criminal justice, whereby political parties vie to be more punitive on sentencing, to no good effect.