Ayn Rand's play, Night of January the 16th, is known for its jury gimmick.
She was reportedly influenced by another play, The Trial of Mary Dugan, which also had a jury gimmick.
The gimmicks are different, but related.
In Rand's play, the jury is drawn from the audience, and they actually vote to determine the verdict of the play.
In the Trial of Mary Dugan, the audience is addressed AS IF it were the jury. And at the end of the play, an actor planted in the audience pretends to be the jury foreman, and shouts "Not guilty."
There is no wall.
It's space, that's all.