To understand what prison does to people, journalist Frank Seibert voluntarily goes to jail. For a few hours, a cell door closes behind him. Isolation and the sudden loss of control change everything, he says after his "release".

What good does imprisonment do? Lawyer and former prison governor Thomas Galli says: nothing! He would release 90 per cent of people behind bars on parole. Prison means social exclusion. But it is also expensive, costing the state some €200 per prisoner, per day. In total, this means the system costs taxpayers over €10 million — every single day. Thomas Galli would rather see that money invested in social work and therapy for offenders.

René Müller has been working as a prison officer for over 20 years and disagrees. Locking up criminals serves the purposes of general safety, deterrence and a sense of justice, he says. Frank Seibert explores the question: Who is right? To find answers, he meets with criminal law expert Kristin Drenkhahn from the Free University of Berlin, who is investigating the effect of the social climate in prisons on rehabilitation. 

Neuroscientist Simone Kühn from the Max Planck Institute in Berlin and psychiatrist Johannes Fuß from the University of Duisburg/Essen are investigating the behavior and associated brain changes of prisoners. This is the world's first research project to investigate whether life behind bars is so monotonous and lacking in stimulation that certain regions of the brain shrink or even become inactive. 

In Norway, the then Minister of Justice asked himself this question back in the late 1980s, when recidivism rates were alarmingly high. To answer it, he convened a group of experts. Lawyer Are Høidal was one of its members. Frank Seibert meets Høidal in a prison near Stavanger. This prison operates according to what's known as the 'normality principle.' This means no one serves a sentence under stricter circumstances than necessary for the security in the community, and that all criminals are treated with respect and kindnessand live in small communities, without prison bars.

Frank Seibert also takes a close look the offender-victim mediation at WAAGE Hannover e.V., accompanying a victim in her process of dealing with a serious crime.

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