I am reminiscing about how weird it was to watch “Three Days of the Condor” back in the late 1970s and thinking, “Oh what an exotic plotline. OUR OWN CIA involved in this treasonous wetwork and other stuff. Wooooooooooooooooo.” LOL.
That’s one of my favorite movies. I watch it over every few years. Another one that I watch every few years is Deliverance. That movie holds up well more than fifty years later.
Are you thinking of “Executive Action”?
https://www.imdb.com/title/tt0070046/
“Rogue intelligence agents, right-wing politicians, greedy capitalists, and free-lance assassins plot and carry out the JFK assassination.”