Leon took his time answering. Silence gave you time to think. It also made the criminal of the day nervous, making him think that you knew a lot more than you did. Of course, this was no criminal. Juvi left evidences in the way you spoke, the way you acted, and while the boy had some of the traits, he was missing too many others. So not a criminal, or at least not one that had been caught, but also used to official figures.
"Foster care made you dislike people in charge, didn't it?" It was that or military school, but again, he didn't behave like a cadet, didn't sit like one either. "The name isn't right, and I know that because that name doesn't exist." They had another G Callen in their hands, and they didn't even know if Callen was his real name. They might both not exist in this reality, but Leon didn't like those sort of probabilities.
"You're also from a different dimension and I know that, because I'm from a different dimension. This is ICIS and I'm the Director. We track down people that arrive here from other realities and then we help them acclimate here. So no, you are not being charged with anything, but you're not allowed to leave either. So why don't we start again? What's your name, son? We'll find out anyway, but cooperation on your part is appreciated."