So now we know who contributed last night's "You Lie!" moment

It's none other than Supreme Court Justice Sammy the Stem Cell Alito:

OK, so he didn't shout it out. He didn't have to. But as John Aravosis notes:

Highly inappropriate for Alito to do this. You'll notice the Sup Ct doesn't even clap when the president enters. They are not supposed to respond to anything, lest it show bias.