George Kerevan: More criminals in jail won't solve our problems

I ONCE spent a year in HM Prison Saughton in Edinburgh. Just for the record, I was not an inmate but teaching a business studies course to those who were, so I got to come home at night. I can still conjure up the pungent smell of hundreds of men locked up together – a lethal combination of sweat, urine, socks and frustration.

This was some 20 years ago, when our jails were much less crowded than today and when hard drugs had not become endemic inside prison. At the time, Saughton still had slopping out and the physical conditions inside were ancient and cramped.

My cla...