and Wikipedia. The world went crazy.
In fact, everything is extremely logical. Breivik’s recognition of his innocence would allow him to be hidden in a psychiatric clinic for the rest of his life. And the non-recognition, on the contrary, would only allow him to be sentenced to the highest degree of punishment. According to Norwegian plush laws, this is 21 years in prison. That gives Breivik a ghostly hope of liberation. A ghost - because after 21 years the court can still leave him in custody for another 5 years if he is found to be dangerous to society. And then another 5 years.
All of this is described in Wikipedia.
Read what you encounter "mnogobookaf" to the end, and the world will become more understandable.