Like Orin Kerr, Marty Lederman, and Mike Rappaport, I believe that the answer to this question is “Yes.” This consensus now covers conservatives (Mike), moderates (Orin), liberals (Marty), and libertarians (me), so it has to be right!
I have a slightly different rationale for my view than any of my esteemed colleagues. Article III, Section 2, Clause 3 of the Constitution says that most of the the Supreme Court’s jurisdiction must be exercised “under such Regulations as the Congress shall make.” Presumably, this includes the power to establish procedural rules for the Court’s proceedings, including such matters as the timing of Supreme Court terms (which is indeed regulated by Congressional statute, as Orin notes). To be sure, Congress cannot use this power to establish “regulations” that violate other explicit provisions of the Constitution. For example, it could not establish a regulation depriving justices of their life tenure, because life tenure is specifically guaranteed by Article III, Section 1. On the other hand, there is no provision of the Constitution that forbids Congress to regulate the degree of publicity accorded to Supreme Court arguments. So the justices would have to obey a congressional law mandating openness to TV coverage of oral arguments – however much it might annoy them.
Technically speaking, this Clause only applies only to cases where the Supreme Court has “appellate jurisdiction” and not to the extremely rare cases (e.g. – boundary disputes between states), where the Court’s original jurisdiction applies. However, even if Congress lacks the power to force the Court to televise the latter, it would still be be able to allow TV coverage of over 95% of the Court’s docket.
On a related note, it is worth considering the possibility that the Supremes’ motive for banning TV coverage is not as high-minded as we might think. Several years ago, the then-Supreme Court correspondent for one of the major TV networks told me that the main reason for the justices’ strong opposition to TV coverage was their desire to avoid being recognized by members of the general public in the streets – especially people who might harangue them about their decisions.
According to this reporter, the justices value the adulation and recognition they get from the legal and political community, but also like the idea of being able to remain anonymous on the street or other public venues. Of course, I do not know if this individual’s interpretation of events is correct or not, though it seems credible to me. In any event, the justices’ desire for a degree of privacy and anonymity (if that is indeed their motive for opposing TV coverage) is perfectly understandable, and I don’t blame them for it. I do not, however, believe that it outweighs the public interest in televising oral arguments.