They have been "fact checking" since 2007, and listed every politician that they've tested so far. On a percentage basis, the biggest liars have been Ben Carson, Donald Trump, and Ted Cruz. The most truthful (and this is a low bar indeed) have been Barack Obama, Martin O'Malley, and Bill Clinton (and they have been untruthful many times)
I'm sure some people will say that these fact checkers are biased (New York Times! Left wing bias!), because we live in a world where even fact checking isn't trusted as long as it doesn't match the reader's already pre-conceived notions of the truth. In another time and place we may actually be able to live in a world where actual facts matter. That time is not now, and that place is not here.
