It wasn't by choice. I do a "movie night" with friends of mine every Tuesday, and they decided to rent JFK (since their son is studying the assassination in school right now).
To be honest I almost left. I've hated every Oliver Stone film I've ever seen. None of them work dramatically or artistically. They are all overwrought, with totally unbelievable characterizations, corny dialog (which is often unintentionally hilarious) and speculation and half-truths presented as though they are fact.
Anyway, I decided to bite my tongue and consented to watch the film.
I almost wish I hadn't. They rented the "directors cut" of the film, which clocks in at THREE HOURS and FIFTEEN MINUTES. That's almost as long as Lawrence of Arabia -- for a movie that is incessantly talky, convoluted, and shot mostly in interiors.
I have to admit that there are some odd aspects regarding the Kennedy assassination which make the premise of this film potentially interesting.
But Stone takes so bloody long to make his case, and gets hung-up on a lot of irrelevant minutia (of dubious importance). William Goldman and Alan J. Pakula were able to tell Bob Woodwood's and Carl Bernstein's Watergate expose within a reasonable running time in All The President's Men. But somehow Stone needs more than three hours to show Jim Garrison's investigation -- an investigation than relied on far less concrete evidence than Woodword and Bernstein's.
I think everyone agrees that Kevin Costner is not a particularly dynamic or versatile actor, and really rather bland. So what could be worse than three hours and fifteen minutes of Kevin Costner droning on and on and connecting a lot of semi-related (if not downright unrelated) dots? Add to this his fake Louisiana accent that silly-looking pipe in his mouth, and I ask myself "How did anyone ever take this movie seriously?"
Moreover, Stone fails to mention that the real Jim Garrison was in fact relieved of National Guard duty owing to "severe and disabling psychoneurosis". (Of course had this fact been included, any semblance of credibility the film might have had would disintegrate.)
Stone's bad taste and appetite for the lurid is freely indulged in the laughable scenes of Joe Pesci whipping Tommy Lee Jones during a sadomasochistic liaison, while Kevin Bacon -- dressed like Marie Antoinette -- looks on approvingly.

But if Stone lacks good taste, he lacks tact and decency even more. I was disgusted at how Stone was so eager to make his point that he had to include the archival footage of President Kennedy's head being blown off. And not just once, but several times, and then showing it again -- and again -- this time enlarged it to give the audience a better view.
Did Stone ever stop to think that Jackie, or John Kennedy's children might see his film? But Stone is so self-righteous, so convinced of the legitimacy of his agenda, that he can justify making what is, quite literally, a snuff film -- a snuff film which exploits the death of a US president. Its sick.
In addition, Stone's integration of genuine archival footage with newly shot 16mm footage (which resembles archival footage) was incredibly irresponsible, and served to blur fact with speculation (his intention perhaps?).
On top of all this is the subplot of Jim Garrison's marital problems, which theoretically contributes a "human" element to the film, but only come across like something out of a daytime soap opera.
And I'm sorry to say that even John Williams' contribution didn't amount to much. In fairness, the film is virtually unscorable, with little room for a composer to do anything. Williams' end title is very well-done, but the film is otherwise so repellent and irksome that I just couldn't embrace the music.
Easily among the worst films ever made, at least by a Hollywood "A-list" director -- and certainly the most boring movie I have ever seen.