Episode 3 "Beatrice's Closed Room Definition"

[zilzmaer]

When Beatrice makes her "Closed Room Definition", and Vergilia starts explaining the closed rooms, the first three are all stated to follow Beatrice's definition (though not stated in red). But then, Battler gets impatient, and Vergilia stops explaining in as much detail, including no longer saying that the rooms fulfill Beatrice's definition.

By now, I'm just past the second twilight, and I have to wonder: Does anyone ever mention that the boiler room (which was stated to be a closed room but not stated to fulfill Beatrice's definition) has another door? One that leads into the courtyard, and cannot be locked? This other door featured prominently in the first episode, and means that the "closed door chain" of the first twilight was not a closed chain at all, as anyone could've set up the boiler room last and just walked through the courtyard to one of the other doors.

[☠Black Knight]

Tbh, I don't remember enough detail about that part to answer your question, but I do remember having a similar feeling throughout most of the question arcs regarding the windows. Windows seem like an obvious point of entry, and most of the so called "closed rooms" have windows. Plus we know from another chapter that there is a ladder in the storage shed that can let someone reach the windows not on the first floor.

But the game treats em like the windows just don't exist. ¯\_(ツ)_/¯

Plus, depending on how the locking mechanism for the windows work, it would actually be possible to re-lock them as you exit, if you had a long object like a stick. But... yeah. A lot of the important details regarding the "how done it" are kinda just glossed over, unfortunately. Mainly because Battler is too dumb to ask the more important questions.

[Ellixer]

I recall the story's definition simply was "no exit from the inside", and regardless of how many ways you can think of to get out the short answer is simply "doesn't work because reasons". So if you say there's a window, the presumed answers are "unused", "locked from the inside", etc. Battler can ask further questions for clarification but at this point he's still an incompetent fool, mostly.

[zilzmaer]

Beatrice's Closed Room Definition
The term 'closed room' refers to a room where the inside and the outside are completely cut off from one another. Naturally, it will be impossible to even affect things across that boundary line, much less enter or escape across it. This includes an all-inclusive denial of the existence of hidden doors, as well as all possibility of intervention from the outside. I refer to all types of direct intervention from the outside, such as using a fishing line or a long, thin rod. In conclusion, there are no gaps in the doors and windows through which such tricks will work. I'll add to this definition that interference due to radio waves and related methods of remote control shall be impossible. (re: phones) All direct and indirect methods of interfering with the inside of the closed room from the outside of the room are impossible. (re: voice or knock) The closed room definition does not cover whether transmission of intent across the boundary is possible or not.

This has been edited to remove Battler's commentary and questions. Prior to the introduction of this definition, they were rather careful to eliminate the possibility of window use, by saying that they were locked from the inside and that no way exists to lock them from the outside. Windows could, therefore, be a point of entry, but one would have a difficult time leaving through a locked window.
This definition also does not seem to preclude lock picks, or any other method of locking a door from the outside, which had been explicitly countered with red every time during episode 2.

[Sergent H]

It's stated that windows cannot be close from outside.
Which make it a lcoked room because the culprit isn't there anymore; the windows are all closed from inside and the doors locked too

[Pay Child Suport]

closed room murders are a staple to any murder mystery genre. don't give too much thought about windows and what have you, because that will kill the entire point of the challenge in solving a closed room murder. it is just exactly what it is. a dead body in a closed room, locked, and the culprit can't possibly get out since the scene was found locked.

there are plenty ways to commit a murder remotely. one famous example is the "cellphone bomb" where you call a cellphone tied to a bomb and its trigger is the cellphone's vibration. but of course, cellphones don't exist in 1986 so scratch that idea.