It would be like calling a carnival barker a liar.
Of course he's a liar, as any observer who pauses and carefully considers the substance of what the carnival barker says can easily see.
But the crowds enjoy having their ears tickled and even though many listening to the barker might suspect the attractions are not really what they are claimed to be, they'll pay their money to see the bearded lady and the reptile man or in this case, Obama the amazing composite thin-skinned man.
Liars use statistics and statistics lie when liars cite them.