A recent NYT piece on the Butler Rally shooter reveals that the shooter (T.M. Crooks) knew beforehand that counter-snipers were posted on the second floor of the second building.
This meant that he knew, beforehand, that counter-snipers would be posted behind and above him — able to look out the second-floor window to see what he is up to.
But this behavior is highly irregular for an assassin to take. Any person of average intelligence would have expected to have been “taken out” before even getting a shot off, because of knowing, beforehand, that counter-snipers would be posted behind and above (where they could see).
It’s so inconsistent that you’d never even find it in a movie screenplay.
Hellbound and Down 