I give those CTers who at least articulate a theory some credit. They have to defend those positions with evidence and arguments even though these efforts fail. In contrast, the CTer contrarians won't even articulate who they believe was behind the assassination. Like Inspector Clouseau, they suspect everyone, and they suspect no one. There is apparently a dim realization that there is no evidence that points toward anyone other than Oswald. Certainly no evidence that points toward anyone else that satisfies the impossible standard of proof that they apply to evidence of Oswald's guilt. That also allows them to take the lazy defense attorney approach by suggesting doubt of Oswald's guilt without grappling with any of the direct implications of their claims having validity with all the obvious absurdity that entails.
Strawman arguments. 6 out of 7 mock trials have resulted in either a hung jury or acquittal in favor of Oswald - in other words, there is reasonable doubt as to his guilt. (The exception was a farcical trial).
We need not know who pulled the trigger or who planned it*. All that is relevant to conclude the assassination was a conspiracy is that the evidence shows that Oswald could not have pulled it off and that it had to be by others. It also doesn't help the lone gunman scenario that a cover-up of the truth by the Warren Commission and certain agencies or departments of the government occurred.
*People can theorize how, who and why after the fact - if the police didn't theorize, nobody would go to jail. There are theories that fit the facts better than the SBT.