Jesus H. Christ, Esq.
Billy Flynn is "the silver-tongued prince of the court room." This dude doesn't just think he's god's gift to women; he practically thinks he is the son of god. He's never lost a case for a woman (so maybe there is some divine intervention), but as far we can tell the only thing divine about Billy Flynn is his tap-dancing skills—and we mean tap-dancing literally and figuratively. His courtroom record has earned him the right to be cocky.
When Roxie first hears of Billy Flynn, she dreams of him as a singing savior, crooning, "I don't care about expensive things, cashmere coats, diamond rings, don't mean a thing. All I care about is love." But expensive things are pretty much all he cares about. The women are merely accessories on his road to fortune. Note in the song "All I Care About Is Love" his car made of women.
He even tells this to Roxie point blank later on:
"You mean just one thing to me. You call me when you got $5,000." She's a price tag, not a woman. Oh, and before you think that Billy is just sexist, we should tell you that Mr. Flynn is an equal opportunity offender. He treats men—like Amos—just as poorly as he treats women. (At least he's fair, right?)
Billy has no scruples about forging Roxie's diary to win her a "not guilty" verdict, either. He doesn't care about men, women, or justice. Take it from Velma Kelly: "Don't forget: Billy Flynn's number-one client is Billy Flynn."
It's the best piece of advice she gives Roxie, because it's the truth… which is a word we're not sure is in Billy Flynn's vocabulary. And he doesn't gain appreciation for truth or human rights over the course of the movie. He's simply $10,000 richer when the credits roll.