That is an artful thesis, at least by Massei's standards, but it fails to account for the distribution of the glass on the floor. You need to add an element to the staging - they broke the glass with the window open, the inside shutter directly behind the window, and the outside shutters closed to prevent escaping glass. Then they took some of the broken glass on the floor and arranged it on Filomena's rug to look as though the shattering impact had come from the outside.
But in carrying out this ruse, they forgot to remove pieces of glass from the clothing which they had previously strewn about the room, as documented by the memories of Filomena and the police, but not by photos.
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Well, here's a photo, from Bruce's site, showing the glass on the floor of Filomena's room....
Glass on the blue rug is what, three, four, five feet from the broken window? Why do you find it hard to imagine glass from the left glass pane being struck by the large rock, bouncing off the interior "shade" and landing and bouncing to their photographed location on the rug (and elsewhere on the floor)? How far the glass fragments fly depends on the speed the rock was thrown, plus many other factors. Okay, I've never myself simulated such an event, but I've dropped glass items on the floor, which broke, and fragments scattered just as far. So, under Massei's staging scenario.....I don't see the law of conservation of momentum violated here in Filomena's room. Or any other law of nature.
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