Slippery managers don't give straight answers. They are masters of vague generalities, continued research, additional reviews, and details - masses of details - on items that do not matter.
"I'm sorry, I thought you knew" is one of their favorite phrases. If pressed, they also employ language that implies prior candor regarding items that have been hidden. [When they say, "As we all know," rest assured that what is about to be disclosed was neither known nor admitted.]
Simple, methodical, and relentless pursuit of the truth is the best way to box in the slippery manager. The facts are against them so they try to elude detailed examination of the facts and cloud their trail with theories, crises, and distractions.
Watch for what is said but, more importantly, watch for what is not said. As with any accomplished magician, their efforts will lead you in one direction when you should be looking in another.
One tip: Ask yourself, "What simple facts do I not know?" and "Do I have confirmation that what has been asserted is the truth?"