Let me preface this by saying obviously Holocaust denial is a heinous and atrocious lie and one of the most damaging in modern history. Understandably you are on thin ice and will be very easily discredited in the academic world if you start to promote denial or anything bordering it. But given that, how can historians tell if someone who is conducting research that turns up lower casualty counts or something of the sort is a genuine scholar or just an anti-Semitic propagandist? Seems like a fine line and not easy to tell but maybe better historians of the Holocaust can set me straight.