It's said that figures don't lie but liars figure. If that's true, then the figuring that they do is how to disguise the truth. There are specific ways to accomplish this. The most blatant was used (but not invented) by the Nazis, and is called "The Big Lie." While that sort of thing has always been popular ("Let them eat cake" is a well-known example), and quite in line with most peoples' instincts to simply deny when accused, or demonize when aroused, there are many more subtle techniques.
Quite a few of these techniques are based upon what are called "logical fallacies." Learning to recognize and avoid these reasoning errors is an important tool when attempting to discern the truth from rhetorical reasoning tricks designed to deceive, as well as when doing one's own reasoning to draw correct conclusions.
Common examples include the "bandwagon fallacy," where the popularity of a belief is substituted for its truth, the "ad hominem attack," where the revelation of a repulsive characteristic of the claimant is substituted for analysis of hir claims, and the "middle ground fallacy," where instead of analysis through to determination of truth or falsity a "middle position" that no one believes and that has no supporting evidence is selected.
Of course, such reasoning mistakes can be also be used as tricks to mislead the stupids. And this kind of dishonesty is worth keeping your eye out for, because it is the signature of a flack. Flacks are the ones who get voted for by the stupids.
There are tools that can teach you to recognize these fallacies. Most of them are lists of the specific rhetorical techniques. Most of them have been known since the time of the Greek city-states, thousands of years ago. They are as applicable today as they were then, human nature being essentially immutable in the short evolutionary timespan since then. Here are some good lists, with definitions and discussions of these techniques:
Nizhkor Project's Logical Fallacy Index
Stephen's Guide to The Logical Fallacies: Welcome
Because nothing is as embarrassing as being shown to be incompetent at thinking.
A good book on the subject is Rudolph Fleisch's The Art of Clear Thinking, but last time I checked it was out of print. We're getting stupider as books like this fall off the edge of the world. And as foundations of critical thought are ignored.
How long until it's required that people be taught to think in school? The traps in these fallacies and the nature of the misinformation they create should be common knowledge. Instead, this is some sort of arcane procedure. The thing none of the naysayer notice is it's obvious to a five-year-old if only s/he will refuse to be tricked.
The truth is as plain as the nose on your face. Note that your own nose is essentially invisible to you despite its presence in most of the visual fields your eyes process and send to your visual processing hardware in your occipital lobes. What you think you see is not always what you see.
Your logical faculty is even more unreliable without oversight than your sight. So I and I say measure twice and cut once. You have the equipment to find out what's really going on, if you take the time to develop it and the trouble to use it.