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I don't comment a lot on threads, mostly just read and follow.
I am curious about the knife. How do they know that it was purchased the day before? It seems like that could have provided potential leads, but...? Seems like there is mixed or confusing info on where it was purchased.
Also, did they say how the killer exited the house? Was it back through the window or through the front door? If it was through the window, are they sure it's the way he entered the house too? (Which direction were screen wires bent? Was there blood on the wires? Had the screen beenfully removed before he went through the window?)
Also, dna technology has changed/improved over time. When was the last time various components were tested?
Did they publicize the clothing at the time of the murders? If he was a mamma's boy, I would guess she would have recognized all the items of clothing from news reports. So, imo, she either has a gut feeling it's him and never came forward or he was old enough to live on his own. MOO.
Could it have been a sick dare? Are the TMPD certain there was only one killer/person in the house?
Is there someone/types of people that the TMPD can't "touch", like diplomats, certain high-ranking members of society, etc.? As in, could they have a good idea of who did it but it is better not to "solve" it?
Rather than either Miyazawa being targeted for themselves or what they did, could they have been targeted in order to hurt someone else in the family, as in a wish to make someone else suffer this loss of the entire family?
Just random thoughts which may have zero importance.
I hope the killer can be found for the sake of the Miyazawa family.
Thank you, Vls. It's so nice to be part of WS
And great post, thank you again. In answer to your questions (apologies for the length).
I'm not exactly sure how they know about the knife but the killer left it there in the house. I imagine the police would've done basic leg work to check where it was available starting in the local area and then eliminated all other recent purchases. As only 1,500 such knives were ever produced, I guess it wouldn't have been so hard to make the connection that one was sold the day before nearby and they couldn't locate the person who bought it.
It seems as if they tracked the knife to a nearby supermarket in Kichijoji. If you check out Part 2 of my full case breakdown, there's a whole paragraph on the knife. But I agree that it's unclear where the knife actually came from. The police don't ever narrow it done more than '46 outlets in the Kanto region costing 3,500YEN.' And yes, it could definitely create leads!
The way he enters and exits the house is also up for debate. It's possible he entered through the front door raising the possibility that he knew the family. It's also possible, of course, that he simply knocked on the door and Mikio opened it unwittingly. The problem is with that version of events is that the killer attacked Rei first who was upstairs asleep. So, how would the killer get past Mikio on the ground floor. I *suppose*, if we run with the idea that he knew the family, it's possible the killer got into the house. Spoke with Mikio. Then went upstairs for a bathroom break or something, then killed Rei. But it doesn't seem very likely. After all, if he's willing to kill the entire family, why wouldn't he just walk out the front door in the morning too? We know the grandmother discovered the bodies. Why would he be afraid to kill her too?
It's also possible he got in through the window (we know a lot of police concentrated on the bathroom window during their investigation). He could've left through the front door in the morning. If I were in his shoes and it was already daylight, that's the risk I'd take versus climbing back out through a bathroom window. Unfortunately, the grandmother can't remember if the front door was locked when she arrived. The police found it locked, though. Whether or not this was the grandmother locking it by reflex when she left to call the authorities, I don't think we'll ever know.
As for the mosquito screen, I think I'm right on saying it was found on the ground outside the house. And there were broken twigs and footprints on the ground beneath the window. Quite possible he did that on the way out if he both entered and left the house that way, of course. I can't give you any more detail than that. Other than to say I think the police found it strange that there weren't many fibres / scuffs on his clothes from climbing through the window.
RE: when was the last time DNA was tested by the TMPD. Unfortunately, we have no answers on this.
Yes, I think they did make their information public. I don't have an exact timeline of when what is made available but if you look at my full case breakdown, you can see the image with every single detail relating to every single he left in the house including his clothes.
And I think you're right, if it's a parent, they might well see their own son in this case. Especially because it's almost certain he would have been missing the night before new years eve and would have turned up home on the 31st of December with a hand injury and, perhaps, a not insignificant quantity of money. Plus, he'd be wearing the clothes of another man that the father/mother never would have seen before. But I think I mentioned in a recent comment, I'm not sure what basis the police have for saying he's a momma's boy beyond him eating string beans and ironing his handkerchief. Without anything more than that, feels like guesswork?
It could have been a dare. But murdering two children and two adults and then staying in the house for hours, logging on to their computer, eating their ice cream and melon, drinking their tea, using their first aid kit, leaving your clothes neatly folded up in the house and leaving the next day in the father's clothes to be pursued by LE in the most notorious family murder in Japanese history... that's some dare. Of course, it's possible. And it's quite possible it was never meant to go as far as it did. But we simply can't know his motives yet.
The TMPD investigated initially the possibility of more than one assailant. But it seems they discard this pretty quickly. I think they would have found more than one set of footprints in the blood, DNA etc. Plus, if you look at the video of the house, it's not an expansive place. Two murderers in that place walking around would've been pretty tight. I can't 100% categorically rule this out though.
Vls, your point about untouchable people the TMPD can't go near; I
wish I could say more here. I really do. (To clarify, it's not like I have insider info on that front. But based on things I've got going on with the podcast, I just can't expand yet). But let me just say, I like the way you think!
And as for the Miyazawa's being targeted almost indirectly; again, anything is possible. Often, I think we look for a tangible link. But it could be as simple as the killer seeing one of the family members and deciding he wants them. And for nothing more than them having the bad fortune to go to the same supermarket as him one Tuesday afternoon. If it was targeted to hurt a relative, I imagine the police would have rooted out that kind of skeleton in the closet. I imagine...