got a book about his trial for father's day

and I recall reading Ruby knew he had lung cancer *before* he shot Oswald, so he knew he wasn't long for this world and had nothing to lose. He essentially died from it a few years later. The easily available public sources say he was diagnosed right before he died. Perhaps. Maybe the jail hospital did make that diagnosis, but I am pretty sure he was diagnosed with it years earlier by his own physician. Something like lung cancer typically doesn't go unnoticed right up until the point it kills.