If you’re ever invited to a carol service in a prison, don’t say no. I can promise you that it will be quite unlike any other carol service you will have been to. Chelmsford Prison’s is held in the visitors’ centre, rated ‘bright and welcoming’ by Ormiston Families, the charity that manages it. We guests assembled a good hour before the men arrived, giving us plenty of time to get through security (quite a business when the party includes half-a-dozen Salvation Army bandsmen and their instruments) and have a chat over a cup of coffee and a mince pie. Our number included the Lord-Lieutenant, a couple of past High Sheriffs, the Bishop of Chelmsford and the Bishop Emeritus of Brentwood, and, besides members of the prison’s chaplaincy team, various outsiders who have shown an interest in the welfare, education and rehabilitation of prisoners.

The VIPs sat in a row facing the body of the hall, so once the men had arrived (in dribs and drabs, depending on which wing they were coming from) and the service was underway we had plenty of opportunity to observe them. As in most institutional congregations there were some keen singers, some uncertain ones (the keen ones helping them find their place in the service booklet), and some total abstainers, not to mention some surreptitious vaping. The overwhelming impression, however, was of total engagement with the proceedings, and when the Bishop of Chelmsford stepped down among them to deliver a moving and inspirational address, they responded with all the respect and perhaps more enthusiasm than the average congregation. But then he spoke to them as individuals, not as an anonymous body of criminals.

A big difference between this and other carol services I’ve been to is that when the men were called up to take a reading or prayers, and when they’d finished, the others applauded, and I took that to be a genuine appreciation of the magnitude of the task those men had undertaken: standing up in front of a roomful of people and speaking unfamiliar words. When the man reading Luke 2:8–14 got to the bit about the shepherds being sore afraid, he interjected ‘and me, I’m terrified’. For the men it was an achievement of a kind they may not have managed before, and as such a step, perhaps, on the road to rehabilitation.

In contrast to the slow build-up to the service, once it was over we dispersed quickly, the men to their cells and the guests out into the street; and that is the main difference between a prison carol service and most others. We’re used to wishing people a Happy Christmas as we go our separate ways, but it’s hard to wish someone a Happy Christmas if you know they’re going to spend it in prison.

A week after the prison carol service we were at the Military Corrective Training Centre (MCTC) on the outskirts of Colchester, not for a carol service but to present some High Sheriff’s Awards. The MCTC is sometimes referred to as a military prison, and most people’s reaction on visiting it is to ask why civilian prisons can’t be like this. There are many answers to that question, the first being the nature of the inmates (‘detainees’ at the MCTC) and their offences. Most of the detainees have not committed criminal offences, but have breached military regulations: the majority have gone absent without leave. The regime at the MCTC is very different from that in a prison, with detainees on the go for most of the long day and not banged up in cells.

The stated purpose of the prison service is to enable prisoners to lead law-abiding and useful lives, both while they are in prison and after they are released: in other words, to rehabilitate offenders and prevent them from reoffending. No one would deny that the success rate is pitifully low. The MCTC has the same purpose but with an impressively high success rate, because it devotes considerable resources – more than would be acceptable in a civilian prison – to useful training that will result in better soldiers and sailors and airmen, or, in the case of detainees who are discharged after they have served their sentence, better trained to find suitable employment.

They are motivated, as I see it, by two principal factors. First, because the Army, Navy and RAF have already invested a lot in the detainees, and with a little further investment in the form of corrective training they can get them back on the right track, and the initial investment will not be wasted. Secondly, there is a culture in the Armed Forces which it is not always easy for civilians to understand: a very strong sense that when someone joins the Forces, and in particular a regiment, they are joining a family; and on the whole, up to a point, we stick by members of our family even when they break the rules and however annoying they are.

The difference between the MCTC and the prison service is that in the big wide world society does not look upon criminals as being members of our family, and has not invested very much in many of those who end up in prison; so why should we spend more money on them than the bare minimum needed to lock them up, out of sight and out of mind. This is not to say that there are not a great many individuals working in prisons to produce the same sort of results that are achieved by the MCTC; but there are not enough of them, and are never likely to be.

The High Sheriff’s Awards at the MCTC were initiated by Lady Ruggles-Brise, High Sheriff in 2011–12, based on the existing system of awards in Chelmsford Prison. At the MCTC they are made on the recommendation of the Commandant to staff who have made an outstanding contribution to the establishment. This year, in addition, we made an award (for what I believe is the first time) to a detainee, thus mirroring the practice within the prison: a soldier serving his second sentence for going absent without leave, who has distinguished himself by befriending new detainees at high risk of self-harm and suicide, and shown himself to possess great leadership potential. He is due to be discharged, to take up a new career using the welding skills he has acquired at the MCTC. Efforts to persuade him to stay on have been unsuccessful so far; if he did, he might even join the select number of former detainees who have gone on to be commissioned and rise to high rank.

From the MCTC we went to an event in Clacton to celebrate the achievements of boys who have completed programmes run by Lads Need Dads. It was a poignant occasion, particularly in the context of visiting MCTC and Chelmsford Prison. Lads Need Dads is one those brilliantly simple and obvious ideas, so simple and so obvious that no one really thought of it until Sonia Shaljean came up with it. But anyone who has worked with children, and in particular with children who have found themselves caught up in the criminal justice system, knows that far too many boys grow up without a positive male role model to follow. If you have spent time in the Youth Court or the Family Court you will know that most of the young people who fall out of education and into crime have either been in care, or live in a family that, for a variety of reasons, does not include their dad.

Sometimes boys will be lucky enough to find a father-figure outside the family: it might be a teacher, or a Scout or cadet leader, but this is less likely for boys from more troubled backgrounds. One excellent father-figure I met recently was teaching carpentry to a boy who was on a Referral Order, which means the boy had had to go through the criminal justice system before he could find the help and guidance he needed. I think he’ll come out of it all right, and will go to college to do the necessary training and get a job in construction, but it’s a pity he could only get there by committing a crime and going to court.

That is why the work done by Lads Needs Dads is so important, and why their achievements have been recognised by, among others, the Centre for Social Justice, the Police Fire and Crime Commissioner for Essex, and successive High Sheriffs. And it seemed particularly appropriate, and not especially surprising, that one of the MCTC staff to whom I gave an award earlier in the day had been nominated for his work with Lads Needs Dads: a mentor himself, but also an active recruiter of other mentors within the Military Provost Staff, of whom it was said that ‘his emotional intelligence, positive role-modelling and mentoring ability have directly helped the charity’s beneficiaries’.

Between them the MCTC and Lads Need Dads have much to offer when it comes to showing how to rehabilitate offenders and, better still, stop people offending in the first place. Rehabilitation is a subject that has been much in the news as a result of the horrific events at Fishmongers’ Hall and London Bridge on 29 November, when two young people, Jack Merritt and Saskia Jones, were murdered by someone attending a workshop they had helped organise for a prison-based education project, Learning Together. They passionately believed in the possibility of rehabilitation for even the worst offenders, and although at first it looked as though the incident might have undone all their good work, it soon became clear that it had raised public awareness of what they were striving to achieve. If we cease to believe in the possibility of rehabilitation and redemption, our society will be all the poorer.