People can appear different to different people the same way that a person with multiple Reddit accounts can be entirely different personas on them.
When we see accounts of someone that strongly conflict with our accounts of that person, our inclination is to believe that our view of that person is the "right" one. This is just an artifact of human's natural sensory self-centrism: you can only see him as the person you have seen him as.
The likely truth, about everyone, is that like a 3D object viewed from a single vantage point, that no one person ever truly knows another.
And obviously, everyone deserves their day in court.