Whenever one of my kids is tattling or trying to persuade me using "facts", I'm almost certain they're employing "propaganda".
Like lots of people - they don't intend to deceive - what they intend is to get their way, even if it means embellishing the truth (because they believe their own version of it). Fortunately, even as teenagers, their schemes are transparent. It's easy to see, because I know what they WANT before they make their argument. Since I know they want to "make brother or sister look bad" - I know what to look for.
I absolutely, automatically assume I'm being lied to or minimally being fed a very slanted version of the truth - from pretty much everyone. I trust my doctor and my dentist - mainly because lying to me doesn't help them. I trust my boss, because we're in the same boat, generally - lying to me HURTS him, because he depends on me.
But politicians lie, because it's their native tongue. I think what astonishes me most is they use the SAME lies, or they tell such head-scratching outlandish lies, you wonder what world they live in.