Should the experience of imprisonment do prisoners good? The retiring Chief Inspector of Prisons in Scotland, Dr Andrew McLellan, poses this question at the outset of his final annual report, published this week.

After reeling off a whole line of negative influences, he yet answers the question with an emphatic yes, for three reasons: if it does not change prisoners' behaviour for the better, more crimes will be committed; turning them from a life of crime will save much public money (spending currently works out at £110 per prisoner per day); and, ultimately, we are all part of the same society and "excluding some diminishes all".

Dr McLellan then turns to the good and bad points of his seven years in office. On the plus side, prisons themselves are vastly improved due to a building programme, though black spots remain; prisoner safety is also much better, despite the overcrowding problem; and relations between staff and prisoners are quite remarkably good, with only 3% of prisoners complaining that they are not treated properly.

The downside is principally the unimproved conditions such as the reception cells ("cubicles") at Barlinnie, and the places where slopping out still persists (Peterhead) or toilet facilities are otherwise inadequate (Shotts and Cornton Vale). Then there is the overcrowding and the lack of things for prisoners to do.

Separately, Dr McLellan describes the "frustrations". Why does it take so long for some things to improve? Top of the list is the state in which prisoners arrive, from chaotic lifestyles usually involving addiction - and to which, usually, they go straight back on release, with no continuing support. After referring again to overcrowding, he concludes this section: "Fourthly, there is no agreement about the purpose of prisons. There is little political consensus and no public consensus. So improvement means different things to different people."

With this background, it is hardly surprising that the Scottish Government believes that bold measures are required to try and improve matters. Whether the package currently proposed, focusing on community alternatives to short sentences, is the right one, or is properly planned, is a separate debate. What the public does deserve, however is that politicians and newspapers who want to join in the debate, especially those who complain about "soft touch Scotland", read this report and make sure they address the question how their own proposals will meet Dr McLellan's objectives and not make things worse.