[Norm Lenhart]

There is. He said so on national TV. No one cared and pretended he didn’t say what he said after Snuffulupogus ‘corrected’ him.

[E. Pluribus Unum]

Something that can be interpreted/spun as a slip of the tongue is not incontrovertible.

Something like a videotape of a speech at a mosque is incontrovertible.