[matt4077]

I believe most European criminal law is divorced from the concept of retribution. Only deterrent, the 'reeducation' of offenders and the active prevention of keeping a dangerous person locked up are valid reasons for incarceration.

On a practical level, I believe the idea is that longer sentences do not provide any additional deterrent. Nor do they provide better opportunities for reintegration. Both effects probably see decreasing marginal utility with longer sentences. Even more practical: most violent crimes are committed by males aged 18 to 30. 18 + 16 = 34.

On an ethical level, European law often relies on the concept of 'dignity' which is ill-defined but (for this purpose) interpreted to mean that even hideous crimes do not justify the destruction of all of a person's future.

[antillean]

So if imprisoning people for beyond 16 years doesn't provide better opportunities for rehabilitation or reintegration, isn't that a reason to continue imprisoning them beyond 16 years in order to protect society from them?

As a family of concepts human rights often rely on the concept of dignity, so all law (or ethics) -- European, American, African, Samoan, Caribbean, Peruvian, whatever -- that is based on or significantly influenced by human rights often also relies on the concept of dignity. But yeah, as you say, the concept is so broad and, without a substantiating framework, generally empty of meaning that I can imagine that (though not how) some could use it to say that even 1) planning and intentionally murdering 77 innocent people and then 2) going on to remain unreformed and unrepentant of it shouldn't "justify the destruction of all of a person's future". (Though, thankfully, as far as I know, people who think like that so far either 1) lack the courage of their convictions or 2) lack the power (or both) to actually impose that view of 'dignity' on any society.)