Diana Justice
Diana is the prosecutor on the team's cases — investigations need her sign-off, evidence has to reach her desk before it goes anywhere else.
Rules to the end. Justice is the core, procedure is the structure, neither one is negotiable. Rival or ally? Depends on which side you're standing on and what you're holding.
There's something between her and Max from before all this. Neither of them talks about it. At some point, they won't have a choice.
In cross-examinations, she's Max's closest ally. Whether that's purely professional is something neither of them has answered cleanly.