I thought it was a pretty heavy-handed coincidence that the gal in the alley who was almost raped by the crackheads just happens to be Smiley's cousin.
You've seen Guy Standeven in something because the man was in everything.

Well it sure as hell ain't Shakespeare.
108 193 23 8114 246* 47.73 22 42

Deus Ex Machina ces out of nowhere to solve the main conflict. No setup. No buildup. Its justthere.
So if you think the wallet is that, then so is the piece of paper announcing exactly when the lightning bolt will strike the clock tower. Would you call "Back to the Future" bad writing?

What I can't understand is
Good point, actually.
If a private venture fails it's closed down. If a government venture fails it's expanded. M Friedman

What I can't understand is
why didn't he immediately say how he ended up with her wallet? Surely, he should've known instantly it was his ticket out once he found out she was his cousin. Not like he had something to lose.

Yo Rumsfield!

Then you clearly don't know the definition of either. It's both. It not only is used as foreshadowing (Chekhov's Gun) when he notices the color and the fact that he picked it up to try and locate the girl, it's the Deus Ex Machina because it was the only thing that saved his life. Coincidences to get characters into trouble are great; coincidences to get them out of it are cheating - It's by the purest definition D.E.M.
"If you say in the first chapter that there is a rifle hanging on the wall, in the second or third chapter it absolutely must go off."
You clearly don't understand the definitions, next time, do some research.
One gay beer for my friend here, because he's gay, and one normal beer for me, since I'm normal.

Exactly, the whole wallet thing is nothing but good writing.
The elements of a movie should connect to each other.
"The Love you take is equal to the Love you make" The Beatles.

^^^ i totally agree. There wasn't even a shot of Jake putting the wallet in his pocket or anything like thatcompletely wrote it off, but because of the color, you immediately recognize it when they find it on him at Smiley's place.

I don't think it's either.
It's actually the opposite of a Deus ex. Deus ex Machina is used to describe poor writing where the author writes themself into a corner, so they say "And then God killed all the bad guys and the good guy won. The end."
It's not quite Chekhov's Gun, because that's usually about something unusual that the writer calls attention to. It would be more Chekhov's gun if Alonzo said "Is that her wallet?" "Yeah, I found it on the street over there." "You should return it." "Yeah, I will" - too much attention.
What it is, and it's understandable if you don't recognize it because it's so rare, is "good writing." This movie is great because of all the little bits and pieces that wind back and forth. For example, when they're heading to see Smiley, you hear Alonzo on the phone saying "Make sure the bathtub is clean" - he's setting up the hit.
Great script.

It is not a Deus Ex Machina.
"The Love you take is equal to the Love you make" The Beatles.

Its both. Chekhovs Gun because its used to foreshadow, and a Deus Ex Machina because it saves Jake.
"One gay beer for my friend, because he's gay, and one normal beer for me, because I'm normal"

Chekhov's Gun, definitely.
R.I.P.
T-DOG

http://bit.ly/1b4OwyY

I don't think it's either.
It's a giant coincidence that he finds himself in the rape victim's cousin's bath tub, when the pink purse is pulled out, but it does work for me.
And I have to admit I was on the edge of my seat wondering just what would happen.

I say it's the latter.
Letty gave Alonzo the idea to use Smiley to kill Jake (it satisfies his warped sense of justice; Jake's rescue gets rewarded by his murder by Letty's own cousins).
The connection is direct, not coincidental.

The latter. A
deus ex machina
would be something that solves the MAIN conflict.

I'd call it Screenwriter's Monkey Wrench. Drop it clunkily into the plot in an early scene, wait till everyone has forgotten about it, then produce it with a flourish later when your script gets all clogged up in the bathroom.

I would say Chekhov's Gun. I mean, there's some element of Deus Ex Machina in there, but if one were to define it as one of the other, it would most definitely be Chekhov's Gun imo

It fits Checkov's Gun. How does it not fit Checkov's Gun?
It was a narrative that was put in early scenes and required in later scenes. Checkov stated that you should remove everything that isn't relevant to the story, and so the wallet was left IN the story and is therefore relevant.
SpiltPersonality

I think you're an idiot.
To the OP - there are elements of both, yet, as a whole, neither. It's more akin to Chekov's gun. Finding the wallet was obviously a hint of an event to come, however, it was the opposite of a lethal weapon.
I think it's a joke

I agree with Crystobal I don't think it's either. In fact by definition of both terms it's neither. Quite frankly I'm fairly certain the OP has no idea what either expression means.
Your's sincerely, General Joseph Liebgott

Not a Deus Ex Machina because it didn't come out of nowhere. I don't know about Chekhov's Gun either, but I think it's similar. I think the right term is "set-up and pay-off" or "plant" (as in it was planted (by the screenwriter)).