Johnson's attourney, McClellan, Johnson's mistress, to name two big ones. Do a yahoo search, type in "lyndon johnson", and see what the first things that pop up are. Watch some of the videos if you dare to discern the truth.
Or you can choose to believe you government would never stoop so low.
We've had a corrupt government since Wilson let foreigners take over our currency in 1913.
If you do the search, watch the video of the interview between Johnson and Dan Rather where Johnson says it was Oswald "and others", and that there were other motivations. Johnson knew that history would figure out it wasn't Oswald and he wanted to get his side of the story out there.
After the interview, Johnson told CBS not to air the interview, and CBS, being the lapdog to Democrats that they have always been, didn't air it, like good little propagandists.