But Furcillo’s claim was not confirmed by any paternity test. Nicholson declined to pursue genetic testing, a decision he has not extensively explained in public but which is consistent with his general approach to the paternity question: he has not treated it as a mystery requiring resolution in the way he treated the revelation about June and Ethel May.
Patrick McGilligan’s biographical research raised the alternative possibility of Eddie King — Edgar A. Kirschfeld, June’s Latvian-born manager — as another candidate. McGilligan’s work suggested that King may have been the actual biological father, but this claim also rests on biographical investigation rather than documentary or genetic confirmation.
June herself, by multiple accounts, was uncertain about the father’s identity at the time of Jack’s birth. That uncertainty — a woman in her late teens or early twenties in a relationship with at least two men, neither of them straightforwardly available — is consistent with the social context of her life at that time and with the documented fact that the family chose not to advertise a specific paternal claim.
What all of this means for Jack Nicholson is that the revelation of 1974, thorough as it was about June and Ethel May, left one major question unanswered. He knew, after 1974, who his biological mother was. He did not know, with any certainty that has been publicly documented, who his biological father was. He chose not to pursue genetic answers to that question. Whether that choice reflected indifference, a sense that the answer would not change anything important, or something else, is not captured in the available record.