Recently, I saw this video concerning two Los Alamos criticality accidents, which took place in 1945 and in 1946. The second accident took place on May 21, 1946. There were eight persons in the room in which the accident took place. The video had the picture shown below to depict those persons. The central character is physicist Louis Slotin. Besides him, we can see in the picture three white men, one black man, two white women and one black woman, all of which are wearing lab coats.

enter image description here

This seemed to me to much too much diversity for a 1946 event. And I was right. Every person in the room at the time of the event was male. In one sense, the picture actually shows less diversity that what actually happened, since only five of those other seven men were scientists or engineers. The other two were a photographer, Dwight Smith Young, who died in 1975, and private Patrick Joseph Cleary, who would be killed in action, as a 1st class sergeant, in 1950, in the Korean War.

Also, I was able to determine that all of them were white. With one exception: I don't know whether Patrick Joseph Cleary was black or white. Can anyone say something about this?


2 Answers 2


If I'm reading this right, it appears that his official military records have him listed as "Caucasian"

Down at the bottom of his entry on his Korean War Project page they have this record, with some editable fields for users to supply corrections:


Home or Enlistment HAWTHORNE, NEW YORK

Birth Year 1925

Birth Date October 9, 1925


Ethnic On Records Caucasian

MOS 2745

The veracity of this aside, information very much like this would have been in his military records, so it should be possible to dig that up from them directly. Of course the cemetery is also listed, but I wouldn't suggest anyone try solving this mystery by "digging up" anything in there.

  • Given Westchester county back then (and even now), Caucasian seems the most likely option.
    – Jon Custer
    Commented Feb 1, 2022 at 19:47

If the Patrick Joseph Cleary born October 9, 1925 from T.E.D.'s answer is the correct one, his draft registration card -- signed on his 18th birthday -- describes him as white with hazel eyes, brown hair, and light complexion, 6'2" tall and 165 pounds.

Patrick Joseph Cleary WWII reg card p1 Patrick Joseph Cleary WWII reg card p2

The 1930 and 1940 U.S. censuses show what is possibly this family: Patrick J. Cleary (father), Margaret (mother), children Mary, Katherine/Catherine, and Patrick J. who are white and of Irish descent. (Click for larger images.)

1930 Census - Cleary family in New York

1940 Census - Cleary family in New York p1

1940 Census - Cleary family in New York p2

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