This is the documentary from the BBC World Service.

So I've just got home after a really long day on one of the secure psychiatric wards.

I'm Jenny Okolo. I'm an occupational therapist and I work specifically in psychiatry in the UK.

I tried out a sensory group.

I help people that might be suffering

from mental health issues such as psychosis,

depression or eating disorders.

I brought some of my essential oils

and I research how to create your own stressful.

I work specifically in forensic mental health.

That's mental health that intersects with our justice system.

I want to dismantle the idea that committing a crime means your life is over.

I've always looked into why and how we can support people instead.

One of the guys gave me some feedback and said, actually, miss, this was really nice.

Like I've never considered this before.

In many countries around the world, prison populations are exploding.

Prisons in the UK are so full that prisoners are being released early, while the United States has the highest prison population in the world.

But in some European countries, something strange is happening. Prisons are closing, and reoffending rates are down as well.

It's all thanks to a new way of thinking about prisons and prisoners.

It's really about assuming that the people are locked up are human beings.

It really is quite an effective system, more effective than just a general prison sentence.

Because you just don't think of the right question sometimes if you're within a system

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