One week before Mel Gibson’s The Passion of the Christ (2004) was released in American film theaters, Hutton Gibson told radio talk show host Steve Feuerstein that the Holocaust was fabricated and “mostly fictional”.[28] He said that the Jews had simply emigrated to other countries rather than having been killed, a view which observers described as Holocaust denial.[28][29] He claimed that census statistics prove that there were more Jews in Europe after World War II than before.[30] Gibson said that certain Jews advocate a global religion and one world government.[28]
Some context for Mel’s father,
https://en.m.wikipedia.org/wiki/Hutton_Gibson
Well this explains a lot.