Is there any consequence for knocking out friendly NPCs?

I was wondering around Detroit looking for stuff to sell, and I noticed that there were a lot of police guards and punks in dark alleyways, just beckoning to have their shiny guns stolen. So, if their body isn't found, is there any consequence to knocking them out? (For the good of mankind, obviously.)

Sometimes guards may appear and you'll have to deal with them. And knocking down civilians doesn't count for the trophies or achievements related.

Heck, even if their bodies are found, you may not even lose any Ghost bonuses. There's only a few periods while in Detroit where you can get the bonus and I assume if the body isn't found during those periods, it's okay. Although, I wonder if the bodies could be found earlier and then found again later with both counting against you.

And I think the police will eventually calm down and return to neutral but I haven't done too much to get them excited.