Mark Gettleson from the Howard League for Penal Reform said the Government's proposals to give ex-prisoners supervision in the community is "an admission that short-term prison sentences are failing".
He added that prisoners are currently "being warehoused in enormous overflowing prisons, rather than being given something useful to do on the outside."
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Ten people have died on the mountain so far this climbing season - four more than mountaineering officials expect in a typical year.
“We can use peace”, the US President told the pontiff in their first face-to-face meeting on Wednesday.
A man with a knife has been arrested near Buckingham Palace in an incident Scotland Yard said was not believed to be terror related.