Lawmakers say DoD undercounts civilian casualties

They certainly did over the past 4 years. Alot of accountability was deconstructed and our oversight infrastructure needs serious repair.

I am sure they do. However, in certain parts of the world, telling who is a civilian and who a combatant, isn't always easy

I would agree with that assessment. It goes all the way back to the Korean War, but became a true art in Vietnam. Inflated body counts and deflated counts on "collateral damage."