I came across this post on Gab, with this picture
The Nashville shooter's shoes changed.
I decided to check the video myself. On this school surveillance video, at 1:32, you can clearly see the shooter wearing one type of shoes. On this police bodycam footage video, at 5:57, the shooter is clearly wearing a different pair of shoes.
Possible false flag.
I believe all mass shootings in US, at least during my lifetime, they all have been false flag operations, (PSYOPs). This one is no different.