The gist of the government edict doctrine at hand in the majority's opinion is exactly this.
It is a precedent-based doctrine that says official works of officials whose work carries the weight of law cannot be copyrighted. This is because the law belongs to the people, from whom its authority derives. Thus, a lawmaker (legislator or judge engaging in lawmaking duties - official works) cannot be the author of their work, because their work (the law) belongs to the people. Copyright protections are granted to authors.
This was precedent established in the 1800s, and has now been upheld in this decision. It seems a quite significant decision in this area.
