The treatment of Nazi supporters in Norway
I can give a recollection of what happened in Norway, the so called Landssvikoppgjøret (literally "The national-traitor settlement", but it doesn't translate well) or Rettsoppgjøret (Legal settlement). Mainly the legal part, as that is what i know best. I'll provide a tl;dr for those just wanting a summary, and alternatively you can just skip part 2 if you want a more complete picture of the social issues without the legalese.
It's, perhaps surprisingly, not a topic that has extensive legal or historical coverage. Landssvikoppgjøret has to a degree been mired in nationalist sentiment and been a part of, or drowned out by, the general national celebrations of victory and independence, and the post-war narratives of defeating and overcoming fascism.
The main treatment of the legal side comes from Johannes Bratt Andenæs in his 1979 Det Vanskelige Oppgjøret (the difficult settlement). This book has coloured a lot of the current view, and he concluces that landssvikoppgjøret
ble gjennomført på en måte som vi kan være bekjent av
Translated, that the legal process happened in a way that we can live with, be sufficiently happy with. His views and conclusions has been somewhat critiqued in later legal and historical scholarship, but Andenæs' book is still the only total treatment of the topic.
1. Tl;dr of Landssvikoppgjøret
In the immediate postwar there was a mass arrest of suspected supporters, this was supposed to happen by proper procedure, but this was not properly done in a lot of cases. In total, a bit under 30.000 (The population was about 3m+) were arrested in the immediate postwar, though many were released quickly. The process lacked oversight and prison guards were often young home guard soldiers, so there were instances of violence and abuse.
In the total process, 46.000 people were punished, and out of these 18.000 were put in prison. 45 were condemned to death in court, 30 of them were Norwegian and 15 were German war criminals, however only 25 and 12 (respectively) were actually put to death.
Ninety percent of the members of Nasjonal Samling (National Unity)[1] were either punished or got their case decided by the prosecution deciding not to prosecute the case. The Party ministers were either shot or got 15-20 years in prison, while party officials on average got three to four years of prison. Ordinary members originally got prison from three to six months, but after 1946 generally just got a fine. They however also lost their citizen rights for 10 years [2] and were typically also punished informally by limiting social and economic relations or actively being discriminated against when applying for state authorisations.
A special group of "supporters" is the women who had relationships with germans. These faced extensive extrajudicial and vigilante harassment and would typically have their hair cut. They also faced extrajudicial internment and similar economic punishment to the NS-members, and those who had married Germans had their citizenship revoked and were deported, though - just the women.
[1] Nasjonal Samling was the Norwegian fascist party, lead by Vidkun Quisling, the nominal head of government during much of the occupation. The whole party was generally perceived as traitors for having conspired and cooperated with the germans, there was a large sentiment even against passive members, the bishop Eivind Berggrav's article "the peoples judgement against NS" is a good example and was widely circulated during the war.
[2] This included not just political rights, but also the right to have any public job that required authorisation and the right to have high positions in organisations or companies, essentially barring them from participating in public or high-tier private positions.
2. The law of Landssvikoppgjøret
2.1 The legal basis
Here i will talk a bit more in depth about the legal basis and the actual prosecution.
The legal basis was §§ 86 and 98 in the Penal code of 1902, which applied to people taking up arms against the state or supports enemies in doing that, and people who contribute to illegal changes of the constitution. However, the maximum punishment was just 10 years.
The Norwegian government had gotten delegated powers from the parliament before it fled to London, and had given provisorisk anordning 3. Oktober 1941 wich made the death penalty available for both of these, and extended it to further crimes by provisorisk anordning 22. Januar 1942. These were supplanted by landssvikanordningen 15. desember 1944, which was the legal basis of the prosecutions until a specific law was made in 1947. Other provisions were also relevant, like provisorisk anordning 4. Mai 1945, which prescribed the death penalty for some war crimes.
These provisional arrangements also made pure passive membership in NS illegal and punishable, as the government was unsure of whether membership alone would constitute "support" under the penal code § 86. Furthermore, members could be held economically liable for any damage the whole party had caused.
The Norwegian constitution § 96 requires there to be a law for anyone to be punished for a crime. A problem here is whether there provisional arrangements had sufficient basis in the constitution to be considered a "law". The Norwegian constitution § 97 says that you can only be punished by what was a crime at the time of the action, which was also a problem with some of these provisions, especially with the increased penalties that were meant to apply to actions done before the provisional laws came into force.
Continued below