Makes sense on the checkpoint mistakes.
When it comes to the houses,
a. Cpl Salinas said he saw muzzle flashes, possibly a person firing, as well.
b. Lt. Kallop ordered a team to take the house
c. The Marines training for clearing a house, especially if you think you hear an AK-47 being ratcheted, is to throw in grenades and enter the room firing multiple rounds. (Best I can tell after doing a litte reading).
d. They entered the second house after seeing an open door from the first house which lead directly to the second house (thinking that’s where the insurgents(s) had gone.
e. Capt. Dinsmore testified that “it’s fairly well established through the (unmanned aerial vehicle) coverage that there were insurgents in those homes.” - I don’t know if he specifically meant the 1st and 2nd houses.
Assuming these facts are true, clearing the first house seems also quite reasonable.
d. They entered the second house after seeing an open door from the first house which lead directly to the second house (thinking that’s where the insurgents(s) had gone.
I think this is going to be the biggest problem. That may not be enough to justify the deaths of the civilian women and children in that house.
This case is, from start to finish, a mess. It's not cleanly for the defense or the prosecution. That should be expected, since the defendants seem to be, at worst, decent guys who screwed up big-time.