Justice is supposed to be blind. Having to sit there like lumps on a log for these propaganda dog and pony shows is dumb. Really dumb. And that goes for GOP presidents too. SCOTUS should not be forced to attend these “How Do You Like Me Now” shows. I never watch this SOTU garbage because I don’t appreciate people peeing on my leg and telling me it’s raining.
It's not mandatory. After Slick's impeachment, all 9 did not show up. This year, I think a few (3?) of the justices did not attend. I know J. Thomas did not attend. He was quoted later as saying he had stopped attending due to the hyper-partisan atmosphere.