Let's look at Alice and Bob. I'm going to emphasize gender roles on purpose, because the gender you were born as is not random.
Bob is a naturally powerful, intelligent, strong man who started his adult life as a solder. Every war he fought in was just and he was always on the good guy's side, and every man he shot was evil and deserved it. Eventually after he is honorably discharged he ends up in a position of high authority, say a criminal judge. He sorts out good people from the bad and doles out what they deserve, and due to his great wisdom he never made a mistake in judgement or caused a miscarriage of justice.
Alice is a weak woman of inconstant and average natural intelligence. She never had what it takes to punish anybody (because of her lack of talents and unremarkableness could she could never end up in a position of authority where she could punish others--not even as a forum moderator who bans trolls) and she was too weak to kill anybody.
Now let's look at the summaries of these two lives.
While everything Bob did was just and morally correct... that doesn't change the immutable reality that he ended up in a position where he did take life and inflicted suffering on others. That does not exactly look like the reflection of someone who lived his previous life as an arhat.
And Alice was fortunate enough where she could never kill or inflict suffering on others... at least in one regard (as a punisher). Even if it was because she never had the opportunity, the fact that she was born in a life without such opportunities is a reflection of something.
According to karma, who got the better life, that is, the life more likely to be reborn as either a better human or a being in the higher realms?