Mr Levy seems to think its ok to accuse the IDF of lies and that he doesn't need to prove it. To know the IDF lied Levy would (a) need to know the IDF knew the truth and (b) stated something different from the truth. But Levy doesn't know what they know therefore cannot be sure they lied. If he was diligent with truth and disagreed with the IDF then he would say they are mistaken, not liars. If I were to play by Levy's rules then I would call him a liar, but of course I would not do that.
High school teacher's union threatens strike (Haaretz)
from the article: The IDF uses propaganda like an authoritarian regime