[Ness has discovered Capone bribed the jury to acquit him.]
Judge: Bailiff, I want you to go next door to Judge Hawton's court, where they've just begun hearing a divorce action. I want you to bring that jury in here, and take this jury to his court. Bailiff, are those instructions clear?
Bailiff: [puzzled] Yes, sir, they're... clear...
Al Capone: [to his attorney] What's he talking about? What is it?
Judge: Bailiff, I want you to switch the juries.
Bailiff: Yes sir.
Defense Attorney: Your honor, I object!
Judge: Overruled.

Al Capone: I want this guy dead! I want his family dead! I want his house burned to the ground! I want to go there in the middle of the night and piss on his ashes!

Jim Malone: You just fulfilled the first rule of law enforcement: make sure when your shift is over you go home alive. Here endeth the lesson.

Malone: Why do you want to be a police officer?
Cadet: To protect the...people and the...p...
Malone: I'm not looking for the textbook answer. Why do you want to join the force.
Cadet: The force?
Malone: Yeah, why do you want to join the force.
Cadet: Because...I...
Malone: Yeah?
Cadet: ...think I could help.
Malone: You think you could help.
Cadet: ...with the force.
Malone: Thank you very much, you've been most helpful.
[The cadet leaves.]
Malone: There goes the next chief of police.

Jim Malone: Why do yo want to join the force?
George Stone: To protect the property and citizenry of...
Jim Malone: Ah, don't waste my time with that bullshit. Where you from Stone?
George Stone: I'm from the south-side.
Jim Malone: Stone. George Stone. That's your name? What's your real name?
George Stone: That is my real name.
Jim Malone: Nah. What was it before you changed it?
George Stone: Guiseppe Petri.
Jim Malone: Ah, I knew it. That's all you need, one thieving wop on the team.
George Stone: Hey, what's that you say?
Jim Malone: I said that you're a lying member of a no good race.
George Stone: Much better than you, you stinking Irish pig.
Jim Malone: Oh, I like him.

Al Capone: You can get further with a kind word and a gun than you can with just a kind word.

Capone: Somebody messes with me, I'm gonna mess with him.

[After blowing away a crook who wouldn't "Freeze!"]
Eliot Ness: Didn't you hear what I said? What are you, deaf? What is this, a game?

Malone: You said you wanted to get Capone. Do you really wanna get him? You see what I'm saying is, what are you prepared to do?
Eliot Ness: Anything and everything in my power.
Malone: And THEN what are you prepared to do? If you open the can on these worms you must be prepared to go all the way because they're not gonna give up the fight until one of you is dead.
Eliot Ness: How do you do it then?
Malone: You wanna know how you do it? Here's how, they pull a knife, you pull a gun. He sends one of yours to the hospital, you send on of his to the morgue! That's the Chicago way, and that's how you get Capone! Now do you want to do that? Are you ready to do that?
Eliot Ness: I have sworn to capture this man with all legal powers at my disposal and I will do so.
Malone: Well the Lord hates a coward. Do you know what a blood oath is Mr. Ness?
Eliot Ness: Yes.
Malone: Good, cause you just took one.

Jim Malone: Just like a Wop to bring a knife to a gunfight.

[Last lines]
Reporter: Word is they're going to repeal Prohibition. What'll you do then?
Eliot Ness: I think I'll have a drink.

Eliot Ness: Never stop, never stop fighting till the fight is done.
Al Capone: What'd you say? What're you saying?
Eliot Ness: I said, "never stop fighting till the fight is done.
Al Capone: What?
Eliot Ness: You heard me, Capone. It's over.
Al Capone: [sneering] Get out, you're nothing but a lot of talk and a badge.
Eliot Ness: Here endeth the lesson.