Why not? If he was "clean" himself, it wouldn't matter if his father was Julius Rosenberg, although I'm sure they'd take a really close look at FM Davis' son.
I do believe there is something in the Constitution about "no corruption of blood" even for Treason. See Art. III, section 3.
There was a poster here who was complaining that she had to provide information about herself so that her son in law could get a low level clearance. I think it was marriage certificate and other information.
FMD was investigated for 19 years that suddenly stopped the year that kennedy was shot. he was a known Communist. He collaborated with other Communists. An admitted pedophile.
Come on, it should have been very hard for him to get DIA clearance.