It is my conviction that there is no basis to assume that Jack Ruby lied- about anything, and for the following reasons:
1) He adamantly insisted on taking a polygraph test. It wasn't because he thought he could beat the machine. It was because he thought the machine would confirm that he was telling the truth.
2) He accepted responsibility for killing Oswald. Even though he had no memory of doing it, and only became aware of it because Dallas Police told him that he did, he still accepted that he did; he never disputed it or denied it. And that meant bearing all the consequences of that, including the death penalty. So, why would he lie about anything? If he was going to lie about something, he'd lie about something that might get him off. Right? So, if he wasn't going to lie about that, why assume he lied about anything else?
3) Lies often involve collusion, and Ruby didn't collude with anyone. He didn't even collude with himself. He had no mindset to kill Oswald. He obviously didn't lie to protect himself since he accepted that he did it. And since he did not collude with anybody, he had no basis to lie about anyone else.
4) There is no reason to think he was a good actor. If you listen to his so-called "death bed confession" he certainly came across as speaking honestly. To me, he did.
5) People often claim that he lied about how he entered the garage. But consider the facts: He really did go to the WU office and send the money order, although I contend that it was earlier. But, there he was, and according to him, it was the crowd gathered at the Main Street entrance ramp that lured him. It is my strong conviction that he was drugged with scopolamine, and the evidence is: a) he looked drugged, unfocused, and disoriented after the shooting, b) he was reported to be mumbling after the shooting, c) he was completely mute in public (even though Dallas Police claimed he talked up a storm and with brash bravado about killing Oswald) d)he NEVER provided a reason why he walked down the ramp except to say that he had no thought to kill Oswald or even see Oswald. It's apparent that he had NO REASON to go down there, that it was a zombie-like action, and scopolamine is known as the zombie drug e) in the 1950s, scopolamine was widely used by the CIA in their mind control programs, which they learned about from the Nazis, and Ruby had a long history with the CIA, doing the gun-running to Cuba, first to benefit Castro and later to oppose him. The point is that there were CIA people with links to Jack Ruby who knew about the use of scopolamine in mind control and had had access to it. In other words, there were CIA people with access to scopolamine and access to Jack Ruby; hence: means, motive, and opportunity. They had the Karen Carlin ruse to get Ruby within short walking distance of the garage. But, how could they get him to make that walk from WU to the garage? It must have come down to suggestion, but to make it certain they had to disable his mind's ability to resist or even consider whether he wanted to do it. Hence, the need for scopolamine f) consider their plan: which was that they were going to tell Ruby that he shot Oswald even though he didn't. How could such a plan work with someone of sound mind? It couldn't. So, they had to disable Ruby's mind to get him to the garage and also to get him to accept that he shot Oswald. Hence, scopolamine. It really was the perfect drug for it. For the plan to work, Ruby had to be mentally disabled, and that meant giving him a drug. You can't convince an able-minded person that he killed somebody. THEY HAD TO DRUG RUBY. And they did.
But, getting back to the ramp, Ruby, even in his death bed confession said that he was lured to the ramp by the people gathered there. (And by that point, he was like a wind-up doll; you could have pointed him in any direction, and he would have gone. So just a slight suggestion was all it took. "You should go down and see what's happening at the police ramp, Jack." That's all it took.
There could not have been a plan which involved anyone opening a door or entranceway for him. That would have been collusion, and the Dallas Police were not going to collude with him. Doing that would have given him something- something exonerating. And they weren't going to do that. The plan was that he enter that way. And Bookhout apparently entered that way, and so, they absolutely needed Ruby to enter that way. And in an extremely credible manner, Ruby said that he entered that way. And there really is no good reason not to believe him.