Norway violated mass killer Anders Behring Breivik’s human rights by keeping him in a “completely locked world” after being sentenced for killing 77 people in twin attacks in 2011, a Norwegian court has ruled.

Breivik took Norwegian authorities to court in March, accusing them of breaching the European Convention on Human Rights by keeping him isolated from other prisoners.

“The prohibition of inhuman and degrading treatment represents a fundamental value in a democratic society,” judge Helen Andenaes Sekulic said in her ruling.

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“This applies no matter what — also in the treatment of terrorists and killers.”

The verdict, which took many by surprise, said the Norwegian state had broken Article 3 of the European convention.

It found that the killer had been subjected to strip searches, had been woken up hourly by guards for long periods and that the authorities had done little to alleviate the impact of his isolation.

“It’s a completely locked world with very little human contact,” the verdict said, adding that there had been no attempt to ease the security “even though Breivik has behaved in an exemplary manner during his time in prison.”

The ruling also said the Norwegian state had not violated Breivik’s right to a private and family life.

A view inside a cell at Skien prison, where Anders Breivik is currently held. Picture: EPA.

Breivik killed eight people in a bomb attack in Oslo in July 2011 before attacking a youth meeting of the Labour Party on an island to the north-west of the capital, killing 69 people.

In March, the case raised dismay among Norwegians taken aback by Breivik’s complaints of cold coffee and microwaved meals he said were “worse than waterboarding”.

State ‘surprised’ by ruling

Breivik’s lawyer said prison authorities must now ease the isolation of his client.

“He must first and foremost be allowed to be in contact with other people,” Oeystein Storrvik told reporters after the verdict.

He declined to say what Breivik’s reaction was to the ruling.

Representatives for the state would study the verdict before deciding whether to lodge an appeal, the state’s defence lawyer Marius Emberland said, adding he was “surprised” by the ruling.

The state’s lawyers had argued his conditions fell “well within the limits of what is permitted” under the European convention, and were more comfortable than that of other prisoners.

One survivor of the shooting on Utoeya island said the verdict showed Norway had a working court system, respecting human rights even under extreme conditions.

“It also means we have to take the ruling seriously and evaluate how we treat prisoners, what abuses they may suffer, and how we avoid abuse,” survivor Bjoern Ihler said on Twitter.

“What Breivik did was inhumane, which is why it’s crucial to treat him humanely. He doesn’t set the premise for how we treat others.”

But not everyone shared his view.

“Hooray for the rule of law and all that, but this is absurd,” said Viljar Hanssen, whom Breivik shot five times, including once in the head.

The state must pay Breivik’s legal fees of some 331,000 Norwegian crowns (A$52,000), the judge ruled.

– with agencies