I could be wrong but I think the Senate makes up its own rules for trying cases. It’s not a real court of law.
You’re right. This isn’t a real court of law. I’m saying that Trump’s legal team can use that Supreme Court case to bolster their presentation.
But this is a political trial and no legal precedents apply. They could convict because Trump didn't use enough hair gel or too much, or because he thought about using hair gel.