Does that assassin deserve all that luxury? Of course not! It's a travesty that he will not be hanged. But, every society lives by its own rules.
Norway and US jail systems can't be compared. Not only Norway's crime rate is a lot lower than ours, it sells huge amount of oil. For all intents and purposes, it's a European version of Kuwait, and that's ultimately the reason why they can afford to be generous. In the Middle East they use oil revenue to build absurdly huge and gaudy royal palaces, and in Norway they use it to build absurdly luxurious prisons. Not sure which one way to waste money is better. Also since ancient times their penal codes have been among most liberal in the world.
Whether their system is better however should be based on a comparative study of the a rate of repeat offenders in Norway and US.