Lyric discussion by cmguido 

Cover art for Criminal lyrics by Britney Spears

anmx is dead on.

This song isn't necessarily about being in love with an actual criminal, but rather someone that you have been warned about. Someone that you know is wrong for you in all ways. But your strong enough to realize it and understand that you'll be alright no matter how the situation unfolds.
This isn't the type of fairytale love that can easily be defined, but rather more of a love thats on the edge, that most people wouldn't risk their hearts for, but your not thinking about the negative outcomes of this love, instead your just enjoying the ride, escaping from rationality. Beautiful song matched with the right artist.