Being the good Doper that I am, I did a little search and did not find any recent threads about this excellent film that I just saw. Not wanting to resurrect zombie threads, near Halloween though it be, I offer this thread.
So, while for the most part I loved the film, there was something that I did not get.
**Here come the Spoilers**
Near the end, when the Dune is killing Gabriel, why does Johnny Casper kill his? What made him decide to do this?
Simple.
Gasper was a guy who prided himself on his idea of ethics and knowing who to trust and who not to. That speech in the beginning gives you an idea what he believes. Over the course of the Movie his own (Bizzaro world) sense of right and wrong is continually tested.
First he is betrayed by Bernie.
Gasper then betrays Leo when Leo won’t give up Bernie.
Mink Laru (The Danes boy) suddenly up and disapears and betrays the Dane.
Tom turns on Leo and joins up with Gasper.
the Dane keeps asking him to betray Tom all the while Tom is dropping hints that the Dane is turning on him.
Dooley and the Mayor switch allegences when Gasper looks like he has the upper hand.
By the end Gasper’s entire world is filled with betrayals and turncoats, the Jungle he refered to. he didn’t know who to trust. When the Dane finally talks him into betraying Tom by inviting him to his house for an ambush he can not handle it anymore.
In Gaspers mind Tom was playing straight and Eddie Dane was now acting the betrayer. He first suggests a double cross then takes Tom out to Millers crossing to wack him, finally he sets up Tom to be killed based on Drop Johnsons confession (Beaten out of him).
But the real question is: What’s the rumpus?
Why don’t you take your flunky and dangle!
In that scene, Johnny Caspar is basically struggling with who to believe. As kingpengvin points out, Eddie Dane has already tried to sell Caspar on the idea of a double-cross, even though Tom seems to be playing it straight with Caspar. In Caspar’s mind, I think this is especially evident in the way that Tom immediately forks up the info on where Bernie is hiding when he first goes to Caspar after Leo kicks him out.
Eddie Dane tailed Tom and picked up Drop Johnson, beat him up and interrogated him – finding out the truth, which is that Tom didn’t kill Bernie. However, at this point, Tom has already insinuated to Caspar that not only has Mink been selling him out (which is true), but that also Eddie Dane is in on selling out his fixed fights (which is not true). But Caspar already sees possible motive, and coupled with the fact that The Dane has already pushed for a double-cross (and Caspar doesn’t care for double-crosses on somebody who shows you good faith), he believes Tom at the end. Clearly he is struggling with who to believe during the confrontation between Tom and Eddie Dane.
As an aside, a friend of mine had a bit part in Miller’s Crossing. The scene is toward the end in which he is holding back Gabriel Byrne’s arms as he gets punched in a hallway. Also, my friend Carl also had a couple of scenes in JFK with Kevin Bacon, Joe Pesci and Tommy Lee Jones where they were all dressed up in costumes and makeup. 
Jesus, Tom…
BTW, Binarydrone, I have to say that this is one of my all time favorite movies ever. And details become clearer upon repeat viewings. I highly recommend repeat viewings!
Caspar: It’s gettin’ so a businessman can’t expect no return from a fixed fight. Now, if you can’t trust a fix, what can you trust?
Tom: Leo gets your sister; what’re you selling me?
Bernie: C’mon Tom, it’s not like that at all. Wasn’t my idea, she’ll sleep with anyone, you know that. She’s even tried to teach me a thing or two about bed artistry. Can you believe that - my own sister! Some crackpot idea about saving me from my friends…She’s a sick twist all right.
Tom: She speaks highly of you.
Bernie: Yeah, well you stick by your family.
Leo: Hello, Tom. You know O’Doole and the mayor.
Tom: I ought to. I voted for him six times last May.
Mayor Levander: And that ain’t the record, either.
Not many truly great movies; this is certainly one.
This is my business… intimidatin’ helpless women is part of what I do.
Are you guys givin Binarydrone the High Hat? 'Cause I know he don’t like getting the High Hat.
Maybe we’ll have tea sometime.
“Then find one and intimidate her.”
“I was in the neighborhood, feeling a bit daffy, so I thought I’d stop in for an aperatif. Rug Daniels is dead.”
“Gee that’s tough.”
“Don’t get hysterical. I’ve got enough excitement for one night without a dame goin’ all weepy on me.”
“Tell me why I came here.”
“The oldest reason there is.”
“There are friendlier places to drink.”
So so glad this finally came out on DVD. (Plus, all the times I’ve seen it before I never noticed Albert Finney’s cameo as the bathroom maid.)
SolGrundy wrote
Yes, wasn’t that cool? I don’t think I could’ve seen it if it weren’t for the freeze frame they did.
O’Gar: Jesus Tom, I was just speculatin about a hypothesis.
Tom: If you want me to keep my mouth shut, it’s gonna cost you some dough. I figure a thousand bucks is reasonable, so I want two.
Leo: So you wanna kill him?
Dane: For starters.
Here’s the script.
I agree with Monstre, repeat viewings are good, almost necessary. I saw the movie three times I realized (and only because a friend pointed it out) that the Dane is gay, and Mink “is his boy”.
Dane: What’s that potato-eater up to?
Thug: Beats me.
Dane: That’s Bernie’s sister, ain’t it?
Thug: Beats me.
Dane: What’s he seeing her for?
Thug: Beats me–
Dane: Shut up. Get lost. I’ll see where the twist flops.
You know If Leo had just trusted Verna and not sent Rug Daniels to tail them none of that would have happened.