Have you seen Sita Sings the Blues? If not, you should. It’s good, it’s free, and you can feel good about using bittorrent for something legal. The movie has these three academics discussing the Sita/Rama legend who constantly disagree with each other over the specifics of what happened, and just how completely dickheaded the various mythological characters were. There is apparently a lot room for interpretation, and it’s pretty fun to watch people have a good natured debate about it.
I’ve been thinking about Star Wars lately (episode IV, A New Hope, if you think I have to be specific) and how it is supposedly told from the point of view of the droids, how they bicker, how R2D2′s constant lying drives the plot of the movie from the very beginning, and how C3PO is almost completely clueless at all times. Star Wars is a story told from a particular point of view by unreliable narrators.

“He says it’s nothing, sir. Merely a malfunction, pay it no mind.”
This brings me to the whole Han shot first thing. It amuses me to think of the different firing orders in the various editions as being the result of R2D2 and C3PO bickering like the academics in Sita Sings the Blues. They are telling the story to whoever they tell it to, and they keep going “Han Shot First,” “No, R2, Greedo shot first.” “No, they shot at the same time. Well, maybe Greedo didn’t shoot at all. Dead bounty hunters don’t pull triggers.” Probably who shot first changes every time they tell it.
The droids they weren’t even in the cantina, so they don’t even have first hand knowledge of the events. At best, they would have heard about Greedo from Han, who is also not a reliable narrator. If you like your retcons to be meta and postmodern (as I do), then you can explain the whole Han Shot First controversy that way; the Mos Eisley cantina shootout comes to us second-hand via two liars and a fool. There is no way that anyone can say anything definitive about the order that shots were fired. We can almost be sure that Han had a shootout with a Greedo in the cantina after he met with Ben and Luke, but even that is problematic.
At the time Han is supposed to have shot Greedo, there were stormtroopers in the cantina investigating a maiming (Ben chopped the arm off mr “Death Penalty in Twelve Systems”). It’s why Ben and Luke left the cantina. These stormtroopers would probably be specifically tasked with law enforcement, and not regular troops. An investigation like that takes some time, even if all they intended to do was round up the usual suspects. So they would obviously still be in the cantina a minute later when Greedo is supposed to have confronted Han. Surely they wouldn’t have let Han just casually shoot someone and walk away. Surely Han was smart enough not to blow someone away right in front of the cops. Even if we imagine that they are the worst, most slackerly investigators it is possible for them to be, even if we imagine that they casually glanced around and left without doing a damn thing, they would still have been right outside the cantina when Han had his little tete-a-tete with Greedo.
A more logical explanation of the whole Greedo scene is that it is something Han made up later, maybe to look tougher or impress Leia. It’s not really important why. Han was a scoundrel, after all, and notoriously so. Lying was par for the course for him. Check out the “oh, please” look Ben gives him over the “Kessel Run in twelve parsecs” line. Further, Han was the only character to see this so-called shootout, and they all left Mos Eisley right after the shootout. It’s not the sort of thing that anyone would have been able to fact check, even if they had been so inclined.

Han, relaxing alone in the Mos Eisley cantina.
Han didn’t shoot. Greedo was a lie.