I try my utmost to avoid making moral judgments as in this person is morally bad because of X or Y, but of course as a human being that's an ongoing struggle. But in terms of making judgement calls, such as that person is carrying a knife and looks angry, therefore I discern he's likely to stab me, and thus I shall meander to the other side of the street - these are necessary and essential.
Still, I'll try and avoid saying that 'the knife carrying guy' is a bad person even if I judge he'll likely do something bad, because I've no idea of his back story, real intentions, mental health etc. Likewise, if there's some murderer, I'll judge his act of killing as being evil, but will try and avoid judging him ipso facto as a bad person. Like [MENTION=14730]Milktoast Bandit[/MENTION] as claimed as a trait of INFJ's in general, first impressions usually give me an immediate and accurate impression of the other person's motives and sincerity - do I trust this person, and if so, how much? Maybe I'll feel like one person is out to cheat me, another is insincere, and so with such people I'll keep my cards close to my chest. I'll adjust myself accordingly and keep my hand on my wallet (metaphorically and literally). I'll try and remain open to adjusting my judgement call on do I like/trust this person, but most of the time it's 'on the money' and future encounters solidify previous gut feelings. Still, I can hold a bias, but fortunately such biases are never locked in stone. There are some people I find hard to read, and until I know where I stand with them, and them with me, I'll play it safe and test the waters before getting too comfortable around them.