I've been playing Dishonored and trying to limit the amount of kills I get to five each.

I've succeeded and yet the game says I have high chaos... Is this a bug?

How strange. I averaged about 10 kills a level (counting the fact that I killed no one during 'The Boyle Party,' so some levels had closer to 20) and still got low chaos.

Definitely a bug then.

That svcks!

I got 11 kills on a few levels and it said low chaos. Maybe it's a bug.

Maybe there are other factors involved.

I've read that, provided you keep the kills under 20% in each level, you should still achieve low chaos. My second play-through achieved low chaos despite me having a few kills in the Flooded District, but most other levels I avoided killing altogether.

Some things contribute to your kills though that you might not have stuck around to witness, like poisoning the distilliery elixir or rewiring any of the security/defence devices. Any unconscious bod left on the floor can suddenly appear on the a la carte menu for rats, and they can 'drown' in the tiniest of puddles too. However, if you avoided these and still got a high chaos result, is there any chance you by accident loaded an incorrect game-save at some point from a previous play-through? Otherwise I too can only assume it was a bug.