Another issue is that the eyewitnesses are going to be momentarily stunned and confused after the gun is fired, which seems like an excellent time to drop the gun and walk out.
Like I said, though, the plan here was to put Michael on a plane to Sicily immediately after the hit, and to keep him there until the heat was off.
You know, that’s another funny thing about witnesses: most of 'em can describe the gun better than the person who fired it. A gun draws the eyes, attracts attention. Drop the gun (which they’ll probably continue to stare at for a few seconds at least) and bail, and you may end up being fairly unmemorable.
But if they get the same set of fingerprints off of some other crime scene, that lets them connect the two cases. Even if there’s not enough evidence to convict in either case separately, pooling them might provide enough. And while archived fingerprints from a random smash-and-grab burglary might just gather dust in a basement filing cabinet somewhere, I would expect that prints from the murder of a rich Sicilian about whom everyone has hunches would be kept in the front of the drawer.
In the “keep the cannolis” one (where Pauly, the treacherous driver is killed), is totally different, the dead body is left in the car. Presumably, the car is registered to some nobody, and since nobody witnesses the murder, the Corleone family has little to fear. “Pauly” is just a low-level soldier, which nobody would miss-“Pauly?-you won’t see Pauly no more”.
The muder of the “turk” and Captain McClusky is more difficult-everybody knows Michael, and he (Michael) was assaulted by McClusky, days before.
Course, given the lack of resources for the police in 1945, just tossing the pistol into the Hudson river would have been good enough.
[QUOTE=Jackmannii]
Besides, you can never count on finding a trash can when you need one. You’d look pretty silly wandering around outside the murder scene with a gun in your hand, looking for a place to dump it.
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Exactly. IIRC Michael walked out of the restaurant and directly into the waiting car - no time top shop around for a dumping place.
I always leave the gun. ( I can’t believe somebody didn’t already say that)
Wasn’t Michael put on a boat?
Let’s just forget about the gun for a moment.
Wasn’t Michael holding a drinking glass and silverware just before the restaurant hit? Wasn’t Pauly in the car with to other guys…who opened the interior door handles with their bare hands?
You don’t just look at the weapons alone for fingerprints, people.
Clemenza specifically tells Michael to put the gun back down to his side and let it slip out. “That way, people will still think you’ve got it in your hand.” Also, he tells Michael to walk, don’t run, out of the place and to not look anybody in the eye but not to avoid looking at them either.
With respect to the Paulie Gatto slaying, in the book Rocco Lampone does indeed throw the gun into the swamp, as recommended by the OP. I suspect it was presented differently in the movie as an excuse for a memorable line.
From IMDB, here’s the section of dialog:
[Clemenza prepares Michael for his meeting with Sollozzo]
Clemenza: [holding up a .22] It’s as cold as they come, impossible to trace. So you don’t have to worry about prints, Mike. I put a special tape on the trigger and the butt. Here, try it…
[Michael takes the gun, but can’t seem to fire it]
Clemenza: What’s the matter, trigger too tight?
[With a loud bang, Michael finally discharges the gun]
Michael: Ow! My ears.
Clemenza: Yeah, I left it noisy. That way it scares any pain-in-the-ass innocent bystanders away. All right, you shot them both, now what do you do?
Michael: Sit down and finish my dinner.
Clemenza: Come on, kid, don’t fool around. Just let your hand drop to your side and the gun slip out. Everyone will still think you’ve got it. They’re gonna be staring at your face, Mike. So walk out of the place real fast, but you don’t run. Don’t look nobody directly in the eye, but don’t look away either. They’re gonna be scared of you, believe me, so don’t worry about nothing.
[while talking, Clemenza takes the gun and begins working on it to fix the trigger]
Clemenza: You know, Mike, you’re gonna turn out all right. You take a long vacation, nobody knows where, and we’ll catch the hell.
I served on a jury a few years ago, the defendant shot someone and the bullet passed through the victim and hit another. The gun was found a few days later near where the defendant was arrested for driving on a suspended license. The ballistics expert that checked the gun against the bullet and said that the bullet did come from the gun. He also stated it is rare to get fingerprints from guns used during crimes. Very few guns have a surface large and flat enough to leave a fingerprint and when most handguns are used, the tight grip required to aim the gun distorts or smudges any potential fingerprints. He also said in over 20 years of police work he had yet to get the fingerprints needed to use against someone in court.
Wouldn’t he have been fingerprinted when he joined the Marines? I thought it was part of the routine induction process (although it may not have been back in 1941).
Correct, and the famous “Leave the gun, take the cannoli” is not from the novel.
The story goes that Mrs Clemenza [who was the real life girl friend of Richard Castellano] ad libbed the “Don’t forget the cannoli” in the earlier scene. Francis Ford Coppola liked that line, and then worked it into the Paulie Gatto hit.
Plus, the Corleones used their newspaper contacts to create a smear campaign that McClusky was a corrupt cop involved in drugs (true, actually), which would have discouraged too deep of an investigation.
That’s not gonna help if your dinner companion goes to the men’s room and comes back armed.
Play it safe - go with him.
Its a gangster book/movie truism (Particularly Mario Puzo’s) that the mark of professional hit is a weapon left at the scene. It is untraceable and infinitely less risky than the chance of being caught with the murder weapon.
Of course that is all back in the “golden days” of gangster fiction. Whether it still applies in these days of forensic technology I don’t know.
Well, boats and airplanes are fundamentally the same thing, in a lot of ways. Except for the flying bit. Boats don’t normally do that unless you do something really weird. 
Michael was in the Marine Corps; fingerprints were taken as a matter of course to help identify bodies. I concur with Freddy the Pig that it was done in the movie primarily to make a memorable line and scene.
Stranger
Still, in the pre-FBI days, I doubt the military’s fingerprint database was in anyway linked up with the NYPD’s database. If they had reason to suspect Michael, I suppose they could ask the Marine Corps to send them over. Of course, if they had reason to suspect Michael, they could have just arrested him and taken his prints when they booked him. In either case, he was having a grand ol time Sicily.
Until his very beautiful wife got blown up by a car bomb.