Anybody else notice that in game it says you have 27 kills but after the game is over the carnage report says you have 30?
And I’ll have 0 betrayals and suicides. Which one is right? the in-game score or the after the fact carnage report?
the in game one is the correct one, i got a perfection a few days back, i had 16 kills as i was counting, the in game confirmed this, the carnage report showed 22, and there wasnt a Rampage in my medals 
Apparently, from what I’ve heard, destroying a vehicle counts as a kill on the final scoreboard, but not the in game one. So if you destroy a Ghost with a person in it, in-game you get one kill, but after-game you get 2 kills. Theoretically, if you destroy a lot of vehicles, there would be a large discrepancy.
That’s going on word of mouth; I haven’t personally tested it.
I noticed this in Reach as well. Don’t understand it.