[aflag]

Even though they were arrested by the police, the site was considered a parody by court and he was acquitted. The case in question is about whether the police was liable for wrongly arresting him, which the court found they are not

[windthrown]

Thank you that is an important clarification. To me the line between legality of the page and practical outcome seems like a distinction that's getting greyer. If I can be arrested and held in jail for four days with impunity, that's enough to scare me from criticizing the police, even if I am confident I might ultimately prevail in court.

[aflag]

Criticising the police is unlikely to get you in jail. Theoretically he was arrested for impersonating the police, which is a crime. It's just that when it's a clear parody, then it's not illegal. That is a bit nuanced, though. And you can see how some officer may get that wrong. By the way, now that this has been tried, it's extremely unlikely you will be arrested or investigating for creating a parody page in Facebook. At this point, they would lose in court if sued for wrongly arresting someone that did this exact same thing.

Anyway, if you do things that are in the boundaries of the law, you shouldn't be surprised if you get arrested.