Nobody could have sneaked past the police. Nobody was hiding in any of the room when the police investigated.
They got there with several men. Chances are some stayed in the waiting room and hallway while one was checking out the bathroom.
You did say no shotgunning, but since I expect none of these to actually work, screw it.
- The butler did it. When the maid first checked the door, it really was locked. He then came out of his hiding place in the hallway, unlocked the door, and threw the key in. He’d already cut through the chain earlier in the day, so he just placed something to make it look like it was still intact - let’s say scotch tape. While cutting the chain, he placed the pliers right on the place with the tape, covered it with his hand, removing the tape and pressing the pliers together, making it look like he’d cut them when he actually hadn’t. When he went to the bathroom, while throwing up, he threw in the tape, removing all evidence of his misdeeds.
- The killer is culprit X. The “body” seen through the window wasn’t actually the victim’s body, but a mannequin dressed up as the victim. The killer set it up by entering through the study window while the victim was in the bathroom. This is also when he drew the ‘V’ and set the chain. He also placed some sort of poisonous substance in the air and left. The victim then closed the study window behind him, only then noticing it’d been opened. When the victim entered the waiting room, the poisonous substance killed him. His body ended up dropping somewhere where you wouldn’t notice him upon immediately entering the room, however. When the butler and the maid walked in, the poisonous substance caused the butler to feel ill, and he went for the bathroom. The killer then simply entered the room from the hallway and impailed the victim on the spear, removing and taking the mannequin.
- The sargeant is the killer. While all of these things did undoubtedly happen, he told the story out of order and reformed the context as such that, if the witnesses were to be asked whether it really did happen, they would confirm it. For example: the doctor had made a blunder earlier in the day, causing the room to be filled with poisonous gas. The doctor passed out, and the butler had to break the door down and cut through the chain to get in. The doctor was saved and everything seemed okay. Later, the killer would simply have to walk in and shut the door behind him. The maid sees the victim dead through the window, the two enter normally, the butler gets sick and the police is called.
Well it’s fine at this point seeing how there can’t be that much left to shotgun at.
The butler never pretended to cut a chain that was already cut. Nobody mistook a cut chain for an intact chain.
Well I could wonder about just where the victim dropped that would conveniently keep him out of view, but…
No fake bodies figure into this story. They really saw the victim’s dead body through the window, in the exact position it was found in later.
The victim died from a stab wound, not poison.
The sergeant’s recital of testimonies wasn’t falsified, out-of-order, or significantly altered from what they actually testified.
Even if he was the killer, there’s only so much he could get away with in the long run. All it would take was to ask the witnesses for their testimonies again.
God.
Damn it.
There were two windows in the hallway. Through the window on the side of the courtyard, the maid used a long stick to set the chain on the door in the waiting room. As for how she shut the door to the hallway - she used a string, attaching it to the doorknob and pulling on it tight, effectively slamming and closing it. She then pressed the window to make it look closed. While the butler was in the bathroom, she simply locked the window. The butler would’ve never had a chance to check.
Hah, well only got yourself to blame. I pointed out every window in every room. Maybe I should just have put them on the map if it was that hard to keep in mind. 
It’s good that you noticed. I don’t think I specified two cause in my head it’s like, just both walls having some windows on them. But no matter, will this really help you?
Guess this one works since it was only confirmed they checked the ones in the waiting room.
Alright then, this may be pushing it in terms of what people would reasonably notice while stressed, but let’s say the windows there had latches that made it very easy to notice if they’re not locked.
The two witnesses also checked the windows in the hallway while on the way to the bathroom and found them locked.
YOU CANNOT STOP ME ANYMORE
Same thing but with bathroom window, butler did it, threw the key in, shut the doors between with string.
Or, even better:
Back to that idea about the culprit first sneaking in through the study window, setting everything up, and then leaving with the victim unknowingly closing and locking the study window afterwards. Then, all the killer had to do was throw the spear through the bathroom window, killing the victim. After that use another stick or a string trick to get the doors between to close.
I will stop this second wind right dead in its track…!
It’s impossible to set the chain through the bathroom window, no matter what kind of device or tool you use.
That’s just too much distance for anything to be precisely managed.
I did say it was a pretty simple one, but not quite that simple.
And now, I think I said in the narration that the spear was pretty crudely made. You’d need a much more proper javelin to have any hope of throwing it with such force.
The killer didn’t throw the spear. The spear was directly thrust into the victim’s chest by someone standing behind him.
Naturally, the bathroom window is too far away to do that from.
Could the map be updated with the positions of the windows and the body? The body placement in relation to the diagram is still something I’m not sure about specifically…
Time to try piggybacking off everyone else’s work 
The culprit is one of the police officers investigating the killing. They locked the door, planted the key, and set the chain from the inside, then waited inside the study. They hoped that when the body was discovered the study wouldn’t be checked, but were prepared to escape through one of the study windows if necessary. Because the butler and maid didn’t enter the study, they instead exited through one of the hallway windows while the maid and butler called the police. When they arrived at the scene to investigate, they discreetly locked the hallway window they had used, completing the illusion.
Easy enough to cut down, if all the windows were locked before all the officers investigating arrived on the scene. By the way, could you confirm that these are all the windows at the scene:
1 Like
I think something like this would deny it, actually:
I also think it was established somewhere a person could’ve only passed through the study windows.
1 Like
Yup, I think I mixed myself up, I was trying to put the culprit in the courtyard to get around that red, but I couldn’t do that and keep all the windows locked when the servants passed through…
1 Like
Welcome to the club.
How about this…?
The window in the bathroom did not lead to outside - instead, it was connected to the study. After killing the victim, setting up the chain and planting the key, the butler left through the study. While in the bathroom, the butler extended his hand through the window connecting the study and the bathroom, locked the study window, and then locked the bathroom window.
Looks more or less right, but you forgot the one in the bathroom. Let me mark that for you.
But yeah, only the study windows open wide enough for a person to enter/leave through. I made a red about that somewhere.
Well the map should rule that out now.
The killer is the maid. After killing the victim, she opened one of the windows, preferrably closest to the door. She also moved the painting from one side of the wall right in front of the window to cover it. The radio was playing to cover up the fact that there was a draft coming from the outside. She then closed the door. Then, from outside, she lightly pushed the painting away, and through the open window, used a long stick to set the chain. She then locked the door and went to the courtyard pretending to find the body. The butler, in his shock, did indeed check all the windows… that he could see. Since one of the windows had been covered by the painting, he never checked it. And thus, they will indeed both vouch that everything was nice and locked in terms of the windows in the waiting room they checked. While the butler was in the bathroom, the maid simply moved the painting from one end of the room to the other, and locked the window. The butler had been poisoned just for that purpose in advance - perhaps she specifically chose an extremely fast-acting poison, which she gave the butler before the events to ensure he had to leave the room.
That trick’s been sort of done here before, except with a curtain.
The two witnesses know all the windows that exist in those rooms. If a window had been concealed by any means - they’d have noticed it regardless. This means that when they say they checked all windows in a room, it really is true.
2 Likes
Just to avoid a silly technicality here, can you repeat this in red?
Nobody was hiding in the study, hallway, waiting area or bathroom from the time the chain was cut to the time the police arrived on the scene.
If you’re feeling particularly generous, add the courtyard to that list of confirmations 
And an optional clarification: can we safely assume that the maid and butler were standing watch outside the waiting area door the entire time until the police arrived? Meaning, one of them couldn’t sneak off to lock their escape route without the other witness noticing.
Time for some ridiculous theories.
Culprit-san simply broke down the ceiling, climbed out through that, and then repaired it again once he was out of the room.
You can replace ceiling with wall if you want, though I guess that’s harder to mask in a way that no one realizes that happened.
Don’t worry, We’re already at the point where I try to be pretty generous. Double-checking for technicalities? Reasonable move. Can do.
Nobody was hiding in the study, hallway, waiting area or bathroom from the time the chain was cut to the time the police arrived on the scene.
And you can safely assume that they would have seen anybody enter/leave then.
Ah… the good stuff.
There has never been an extra entrance into the room. No human ever entered or left the room by any other means than the door in the waiting room or the two windows in the study.
The killer is… the maid. She was the masked person that came in the victim’s office. She talked to the victim, and took the key to the room off him. She also left the window to the study open for herself. While the victim was in the bathroom, she snuck in through the window, set the chain in the waiting area, drew the ‘V’, turned the radio on, and left the door slightly ajar. She then exited through the study window (again, victim is still in the bathroom - the victim was probably poisoned beforehand to cause bad digestion). The victim comes out, sees the window, closes it. A loud station on the radio comes on and the victim moves to the waiting area. The victim sees the ‘V’ and is shocked. Victim sees the maid in standing in front of the door. He doesn’t understand. She tells him to look behind him - he does, and in the moment - she stabs him through the gap in the door. Victim spins, losing balance, and then falls over. Maid then shuts the door, locks it, stages the scene with the butler, and then simply plants the key after the fact.