Crackdowns on J-League supporters in Japan have become very strict lately

Regardless of whether it is their own club or another club, any slander results in mandatory fines, entry bans, and lawsuits.
They are catching a huge number of people by monitoring not only banners at the stadium but also real-time internet activity.
J-League fandoms on social media and online communities are expressing outrage, claiming that their freedom of expression is being suppressed.