I guess, it would be easier, if I hadn't cropped the picture a little - it showed something which could lead to the solution pretty quick...but the uncropped picture will be my second hint. ;)

Second hint: same picture, but uncropped...should give people an idea, who this is.

OK. It's from Thief ... but what was the name of the antagonist?

sound? :P

Not that I've ever gotten that far, nor do I think I ever will, but is that the Trickster?

Nope. It's not the trickster.

Final final hint: The person depicted is one of the city wardens and direct boss of Lord Bafford.

I truly don't know what other hints to give...I'm surprised players of this game haven't come up with the solution so far.

Do you know how long ago it was that I played that game? I don't remember that guys name and I would have to google for it. But googling is against the spirit of this game.

I think googling is fine if it's based on clues and guesses, as opposed to just letting google search for the image. If you know who it is and just don't quite remember the name, personally I'd say it's fair to do some research. Definitely better than leaving someone hanging for days. After all, what use is the spirit of the game, if there is no game anymore? ;)

This! Of course you can google the name.
The only thing that would "break" the rules, would be if you do a picture search.
But I already prevented that, by doing my own screenshot - what Google can't find, Google can't give away. :)

OK. In this case: Ramirez. No way I would have remembered that name.

Bingo!

Next one.

I know it...but I won't tell... ;o)

I know her! We get the same bus