In fact, “I hate to be the one to tell you this” (like its cousin, “I hate to say it”) is one of them. Think back: How many times have you seen barely suppressed glee in someone who — ostensibly — couldn’t be more reluctant to be the bearer of bad news? A lack of respect from someone who starts off “With all due respect”? A stunning dearth of comprehension from someone who prefaces their cluelessness with “I hear what you’re saying”? And has “I’m not a racist, but...” ever introduced an unbiased statement?

These contrary-to-fact phrases have been dubbed (by the Twitter user GrammarHulk and others) “but-heads,” because they’re at the head of the sentence, and usually followed by but. They’ve also been dubbed “false fronts,” “wishwashers,” and, less cutely, “lying qualifiers.”

I don't quite agree with the piece, as I think the use of rhetorical tools doesn't accurately indicate that someone is lying. Many times they're just mimicking others.