I think this is because its hard to prove a negative
?????
I do not see how that applies to Paul Irey’s forensic conclusion the the WH pdf BC is a forgery. That is a positive assertion of fact directly backed by evidence, not proof of a negative.
Irey does not prove that Obama does not have a BC in the HI archives, but rather that the claimed pdf image is not a genuine HI 1961 BC typed on a single typewriter of the era, as it should be.