The majority opinion of the Supreme Court decision in the Kanazawa City Hall Plaza case understands that even public properties that are part of the city hall , not "public facilities used for assembly" , constitute "restrictions" on "freedom of assembly."
Public property theory determines the existence and degree of legal utilization rights. If the act of using a public property based on the right of use is an expression activity, it is protected under Article 21, Paragraph 1 of the Constitution. It is questionable whether it is necessary to use the public forum theory just to say this, and the term public forum itself may no longer be necessary. On the other hand, there is still an argument to derive some legal effect from the nature of the public forum, and the term "public forum" is of course necessary here.
This ruling is a case in which the government's interest, which has not been clearly stated until now, is to prevent the attribution of expressions to the government from causing damage to political neutrality due to the government's endorsement of expressions by private individuals. A ban on the grounds that protests from citizens who have witnessed a assembly will cause "impediments" to work should not be allowed as it could be against the premise of constitutional democracy and the protection of freedom of expression. Even if the endorsement of expression, attribution, and prevention of damage to political neutrality were the "important objectives," the physical shape of the plaza, traditional usage practices and the ambiguity of the criteria for determining legality existed in this case. However, once the Supreme Court decides to judge the nature of a facility as a "public facility" (used for assemblies) based on its "physical form" and “traditional usage practices”, the general public's impressions (i.e., social conventions) will change accordingly. However, it could have been possible that the city of Kanazawa would no longer be recognized as endorsing the expression of private individuals holding assemblies in the square. It is considered that the future-oriented judgment should have been made. Therefore, if there is a similar case in the future, the judicial precedent should be changed.
The symbolism of the Town Hall Square increases the value of freedom of assembly and can lead to the recognition that there is no substitute facility in the balancing of interests, the profits lost are great.
The Uga Opposition Opinion expresses the position that the legality of public facilities should be determined according to “their physical form” and “traditional usage practices”, and also has a certain degree of constitutionality and legality regarding the refusal to permit the use of public facilities on the grounds of the fear of hate speech. It was suggestive.
The above is the current stage of constitutional protection of freedom of assembly on public property in Japan in 2023, obtained from the analysis of this judgment.