We live in different legal systems. Sometimes I also have a lot of questions about the laws of the United States, because Trump has signed a lot of executive orders to ban Huawei and TikTok, without going through the court or Congress, and they are effective.

Back to Hong Kong, the Hong Kong National Security Law is not retroactive:

> Article 39 This Law shall apply to acts committed after its entry into force for the purpose of conviction and imposition of punishment.

https://en.wikisource.org/wiki/Page%3AHong_Kong_National_Sec...

The police found evidence that he violated the law after the National Security Act was released, so they arrested him. I wait for the Hong Kong police to release more information.

YouTuber is just one of my information channels, and I also go to the websites or forums of protesters.