Just as it is illegal to post the grades of students with personally identifying information (without prior consent), it’s illegal to administer an oral exam with spectators.
I’m not a lawyer, but my reading of the plain-language summary of the bill is mighty unambiguous.
As long as the defense is genuine, in which student performance is being evaluated, and there a nonzero (though infinitesimal) probability of failure, then it cannot be public unless the student has specifically waived privacy.
I understand that the public grilling of doctoral candidates may be a time-honored tradition.
However, the overt violation of FERPA can threaten federal funding.
Departments that publicly evaluate the performance of doctoral candidates in public are, at least in theory, putting the university at risk.
After all, the thesis must not only be written but also defended.
Therefore, you need to prepare a speech on defense carefully.
More often, committee members may be concerned about the appearance of collegiality and don’t want to be seen as unfairly attacking an unprepared student.
If a student hasn’t truly done the work meeting the standard for the doctorate, the levy of that assessment would be unnecessarily cruel in public.