Some interesting theories but one major error...
I saw this on Netflix and only chose to watch it based upon the year it was made. I had not previously heard of 'Mortal Error' or, surprisingly, this theory of friendly fire. My opinion about the JFK assassination was solidified in the 1990s after reading Gerald Posner's 'Case Closed'.
After watching a few minutes of this documentary, I have to say I was intrigued. However, one major false point the film and book bring up is that Oswald only had something like 5.4-5.9 seconds (I don't remember exactly) to fire all three shots. This has been proven false from a number of sources (including the some of most crazy conspiracy theorists) which show Oswald had more than 8 seconds to fire all three rounds.
If you agree that the first shot happened and missed at, or close to, frame 188 on the Zapruder film (prior to when the motorcade was behind the sign), and the fatal shot was (obviously) frame 313, then Oswald had closer to 8 seconds to fire, not less than 6.
I'm not saying that 'Mortal Error' doesn't bring up some fascinating points. I was actually enthralled with this film up until it proclaimed that the x-rays were doctored and The Warren Commission covered up a some testimony and purposely ignored some evidence.
To be honest, a cover-up by the Secret Service doesn't seem that far-fetched to me in light of the current events surrounding their incompetency during The White House fence-jumping and the South America prostitute scandal. It also isn't that hard to believe that the Secret Service would go out of their way to protect their own. Cops do the same thing.
The problem believing most conspiracies is the necessity of X number of people involved in the conspiracy to remain silent on the event at hand. In regards to all government conspiracy theories, I personally have a hard time believing that the government is competent enough to cover up said conspiracies. In my opinion, the government is just too clumsy and bureaucratic to allow claimed lies to remain lies.
Again, I enjoyed this film and it definitely made me want to go back at look at all the evidence again just to brush up on my history. I believe one reason I gave this film (and book) some credit is that it agrees that the "single-bullet theory" is fact. Any conspiracy theories (as well as movies like 'JFK') that try to claim the second bullet zig-zagged based on a typical car's seating arrangement, I completely stop reading or listening. This tells me the author/filmmaker intentionally or unintentionally fails to acknowledge how the Connallys were positioned lower and to the middle in front of the Kennedys in the 1961 Lincoln Continental.