Okay: That three empty cartridge cases were allegedly found by the so called snipers window.
I'll assume that you have used the word "allegedly" because there is good reason to doubt that there were THREE shells there when Mooney first discovered the shells.... And yes, I know that it is widely accepted that there were THREE shells there, but there is also evidence that indicates there were only TWO spent shells....And all of the documents that originated in the TSBD that afternoon state that there were TWO spent shells found.
A quote from Garrison's On the Trail....
An extremely large Oak tree made it unlikely that the first round fired would have hit anything more than a limb or a handful of leaves.
Moreover, Oswald had been seen in the lunchroom down on the second floor of the TSBD less than two minutes after the shooting. He not only appeared composed and relaxed , but was drinking a Coke which he had bought from the vending machine. For him to have finished his historic shooting feat ( causing eight wounds in two men in less than six seconds) then hidden the rifle beneath the piles of boxes which officer Weitzman described *** and then run down four flights of stairs, then stopped for a Coke at the vending machine ---all in less tan two minutes, without losing his breath ---would have had Oswald moving at near the speed of light. , *** piles of boxes which officer Weitzman described *** and Tom Alyea's film clip confirms....
The conspirators realized that the feat attributed to Lee Oswald was impossible.....Unless they could re-enact the feat and show that Oswald had simply dashed by the site where the carcano was found, and hastily dump the rifle as he passed by....
And that's exactly what they attempted to do.... Unfortunately for them, ( and fortunately for us) Tom Alyea's camera captured the scene of the rifle lying on it's left side on the floor. The preceding scene from Alyea's film shows DPD detective Studebaker perched atop boxes of books just after he finished taking the in situ photo of the carcano. Since the next scene on Alyea's film shows the rifle lying on it's left side with the leather sling up as Detective Day reaches out to pick up the rifle we can be absolutely certain that the in situ photo that detective Studebaker had taken showed the rifle lying on it's left side.
What's the point you ask..... The official DPD in Situ Photo depicts an entirely different scene..... The official government approved in situ phot shows the rifle in a location that is closer to the stairs and the rifle is NOT lying on it's side. And Furthermore....Tom Alyea said that it was obvious that the hiding place had been prepared BEFORE the shooting.
Alyea didn't realize that he was 100% correct on that point...But he didn't realize that the rifle had been placed in that hiding place at the time the hiding place was constructed. And that's where the carcano was at the time of the murder of president Kennedy.