In the next day, I went to buy a wiretapping detector in Akihabara, as I was so nervous of my environment after noising from the upper room. I was accustomed to the life with bugs but I could not have imagined it was opaquely conducted by the authority in Japan, though I thought it was worthwhile to check its reality.
When back to the room, the detector reacted that there was a wiretapping located at one of the plugs. Then, I went to the hotel management and asked them to open it to confirm it.
I saw a small device there but could not discern whether it was what I looked for or not. In my image, the bug consisted of the electronic substrate with a transmitting structure, but it was a small box inside the plug. It did not look like a wiretapping and I eventually realized that I had no knowledge to confirm its authenticity.
Later on, I studied these methodologies and understood there were many ways to eavesdrop on my speaking. You can listen to a conversation in the room with a concrete microphone from the upper or next room. If you employ a directional microphone, you can listen to it from far away. There is said to be a mix of those to listen from far away through the wall. The wiretapping is unexpectedly easy, which is often conducted in any countries.
In the Japanese legal system, a wiretapping itself is not a crime. It is a crime when trespassing and destructing a property when setting up the bug. Furthermore, the police is not allowed to wiretap without a warrant from the court, but I am pretty much sure they have conducted it without notice.
It is apparent that the wiretapping information cannot be treated as an evidence unless it is permitted by the court order. However, if they have no intention to arrest the subject, they can employ any measures. If their original target is to intimidate the subject subdued under their rule, they can do whatever illegal investigation they want. It is unconstitutional, but there is no law that the illegal investigation is categorized as a criminal activity.
Back to the story of the bug in my hotel room, the hotel management has no capability to open the plug, hence they asked an outside help to execute its job. As said, I realized I had no capability to identify it and went out to the convenience store afterward to buy something to drink for my refreshment, where I saw those contractors also.
They talked to the uniformed police officer there and realized they were connected originally, though I had no idea what it meant at the spot. I had not assumed the police was highly involved in the illegal activity and not expected that the wiretapping was so commonly deployed by them in those days.
Moreover, I had still not realized there was a joint operation of the whole intelligence organizations, but expected they run an investigation separately with sharing information.