“Stop shooting yourself, stop shooting yourself!”

Taking the gun from Shanna, as JJ is on his way to doing, clearly carries risks. Even a nervous shooter might’ve found the killing instinct in that last second before he seized her wrists and threw off her aim. But JJ relies partly on his sense of people, and he’s assessed, correctly, that Shanna doesn’t have it in her to kill, no matter how just the cause, no matter the risk to herself and others if she doesn’t. At least, that’s how things are at this moment in time. People do change.

What would’ve happened had Xan not pulled himself together behind JJ’s back? I think it’s a bit better if we wonder. It’s not inconceivable that Shanna could’ve cracked when her only options were “renounce the story or die immediately.” By giving her an out and setting terms for her survival, JJ is effectively playing good cop and bad cop. It’s also possible that she could’ve found the strength to squeak out a “No,” in which case, she would’ve won a small moral victory and literally no other victories. JJ would’ve sighed, shot them both dead, and started the process of covering his tracks.