I waiver on this issue, but most of the time, I'm alright with the status quo. If we want the status quo to change, we should always ask, "How is the change beneficial?" I only hear one reason being thrown out there - transparency. (Obviously, if there's another reason that I'm missing, please mention it.) However, I think this fails under scrutiny.

Many commenters note an apparent absurdity in the Court's policy. "All of the information is already out there!" We get transcripts and audio of oral arguments. Rather than undermining the status quo, this undermines the transparency rationale. What is more transparent about having cameras versus having transcripts/audio?

I think there is something, but it's not pretty. I was finally able to attend the Supreme Court for the first time last year. It was only for opinions, not an argument; nevertheless, I did realize that there are unique qualities of the experience.

1) The general DC grandeur is reflected in the design of the courtroom.

2) Security is annoying, but probably necessary in an open setting where the general public outnumbers the Court members and Court officials several-fold.

3) There is a bit of ceremony and a methodical pace to business. For interested parties waiting on opinions, there is a moment of incredible anticipation (I am not lying when I say that my heart skipped a beat when I thought we might get a really big opinion).

4) The Justices are people with mannerisms. For a time, one justice had kicked back in his chair, hands behind his head, while other business was being conducted. Was he checked out, because his attention wasn't needed for this part of the process? Was he deep in thought about something else? Who knows. I'm bad at interpreting body language.

Anyway, the first three items pretty clearly don't give us anything meaningful in terms of transparency. Even if you construct an argument that there is something in these items (cue Dahlia Lithwick writing an article claiming that SCOTUS defers to government security because that issue affects them), putting cameras in for regular Court business is overkill. The first two items could easily be shared with a "get to know the Court" video which just shows off the courtroom and a "what to expect when visiting" video which describes the security procedures and the decorum expected of the audience. You can get a feel for the methodical pace through audio, and I really don't know why anyone would argue that my schoolgirlish anticipation is an important element of government transparency.

Thus, we're left with the mannerisms of the Justices. I will freely admit that there is information here, but it's ridiculously hard to make good sense of. Perhaps I'm committing the typical mind fallacy, but I'm personally really bad at interpreting body language and facial expressions. I've been close friends with people who feel as though they're constantly misinterpreted. One individual said that when she's working intently on something, people often interpret her facial expression as being mad. They'll ask her if something is wrong. "It's just my face! I can't help it!"

Historically, I always recall stories of when presidential debates moved from radio to television. I've never heard someone make an impassioned defense of all the good things that televised debates gave us. I've personally heard far too many superficial and completely vapid comments concerning the visuals provided in a debate. (Nevertheless, I think it's far more likely that someone could make a good argument for televised presidential debates than televised SCOTUS business.)

tl;dr Everyone agrees that putting cameras in the Court would be technologically easy. It's rhetorically easy to identify "technologically easy" with "beneficial". I haven't heard very good arguments for why there would be strong benefits.