Although cameras showed that protester Bassem Abu Rahmeh was hit by a tear gas canister, Israel decided there is "no evidence" for any action against his killer.

Things like this don't happen by accident. Soldiers are trained to aim their tear gas weapons at the ground, not at people; when the canisters hit people, that's not a minor error but gross misconduct. Deadly misconduct, in this case. The army investigators know that and choose repeatedly to disregard it.