It means there is more than one version of facts and they can exist side by side. It can also mean parallel truth and parallel evidence, in a sense.
"I saw a baseball game yesterday when I saw a guy hit two home runs, I said. Really? I went to that game with you but I only saw him hit one home run, my friend said." What we have are parallel facts. We both are saying actual facts that happened, I replied."
by Magnumb,Private Eye September 15, 2022