Ah, but that's what I'm doing - it isn't just the prosecution entrusted with that particular task, after all.

[He's got no idea what you think he'd be doing if not that, unless...hm.]

Our court system is heavily skewed against the defendant - they're assumed guilty until proven innocent, rather than the other way around. I would think that ensuring the actual guilty party is found out and punished for what they've done counts as "putting bad guys behind bars," wouldn't you?