A new rule for journalists.
End the interview on the first egregious lie.
Turn the lights out, switch off the recorder, get up and leave.
And your report should state clearly that this is why the interview was terminated.
It never should have been tolerated in the first place.
@davew I have a friend who keeps saying that "at least he answered questions”. Ugh. It doesn't matter to him that every "answer" was an outright lie.