Is this also sculpture?
Yes.

The figures are in high relief.

Even the surfaces of the chairs and the littered table are massive, and the eye travels without weariness, as it should do in sculpture, from the hero to the furious woman, then to the attorney behind her, then to the two other revilers, then to the crowd in three loose rhythmic ranks.

The eye makes this journey, not from space to space, or fabric to fabric, but first of all from mass to mass.

It is sculpture, but it is the sort that can be done in no medium but the moving picture itself, and therefore it is one goal of this argument.
But there are several other goals.