What do we want from our prisons these days? Are they to be places of painful repentance, or the holiday homes of tabloid lore? Do we incarcerate people only to punish transgressions, or to help them towards rehabilitation?

It seems amazing that we are still asking such questions after so long. Then again, do-gooders have been pressing for improvement in our jails since Victorian times. It is not so long ago that Scottish jails were forced by European law to finally end the foul practice of “slopping out”.

The Scottish Prison Service has at times attempted enlightened reform. The radical departures of Barlinnie’s “Special Unit” promised so much, yet ended abruptly in the Thatcher era, when the mood swung towards more punishment, not less. The system seemed to have gone back in time by the late 1980s, when a succession of riots revealed a model mired in the bad old days of us and them.

At present, governors are back trying new ideas, particularly working with men who tread the path to freedom near the end of long sentences.

In the street, the mood has changed too. Police Scotland’s Violence Reduction Unit continues to make its mark, helping to reduce knife crime and actively engaging with gang members, among others.

They take some inspiration from Gregory Boyle, a Jesuit priest posted to South Central Los Angeles, an area dominated by Latino gangs and African-American poverty. Later, the district was to explode into massive riots over the police beating of Rodney King.

Fr Boyle began a dialogue with gang members. Not even the most optimistic social worker could have forecast what would come of that intervention. He opened a school, as many had already done jail time and been excluded from mainstream education. He persuaded them to confront the realities of their lives, and the futility of gang membership. He started a service removing the tattoos that had unhelpfully identified them to rival gangs in jail.

That service became a business, Homeboy Industries. Fr Boyle, better known to his charges as “G-Dog”, started a bakery at first. Homeboy supplies all the catering at LA city hall and runs two cafeterias at LAX airport. Thousands of troubled kids have been through the businesses, finding their own path back to work or recovery, and sometimes both.

He was in Glasgow recently to reflect on the Homeboy story. Many former gang members are on the payroll now, some in senior positions. They have a sense of purpose. Recidivism is extraordinarily low, although Fr Boyle cheerily admits to his failures. He wouldn’t be a Jesuit if he lacked self-criticism.

We have a lot to learn from Homeboy. Where better to start than in Glasgow, with a significant part of its community disenfranchised from the modern economy? Our social inequities are shameful and economically wasteful. These things can be changed.

Fr Boyle recounts the public speaking advice he received from one of his loyal aides at Homeboy, a reformed gang member helping to run the business: “Remember, the trick when you’re talking to people about Homeboy is to be self-defecating,” he counselled, blind to his malapropism.