well some drinks seem to have certain chemicals in them that seem to do strange things to people..eg. there is one beer in the UK they call the "wife beater" (i won't say the brand), because a lot of people who are fine on other brands suddenly get violent on this brand...it may be similar with spirits..only the question remains, as always with alcohol, it it really the alcohol that does it or some deep underlying trait which is there anyway, only hidden and brought out by drink..?
but that is a philosophical question..
take care