Kireh realizes she made a mistake. Some of the suspects are trying to lie to her with their thoughts. Not successfully, but she can imagine a future optimization-race between her techniques and criminals' deliberately-muddy minds. She doesn't like muddy minds.
She thought this project was just a way to make money and establish a reputation, so she could gather followers later, for her to shape as she's used to shaping her petitioners and summoners. She didn't think about how it would impact Marra's interests over the whole city.
It might not be that bad. The innocent try to bare their minds to her, if they're not too afraid, and it would be great if people who expect to be innocent in future interactions with the Bristol police practice clarifying their minds ahead of time.
And Marra Herself might be willing to discard criminals into the pits of ambiguity and self-deception. They are, after all, mostly less Lawful and thus less useful, less likely to be awesome. (Maybe Marra even predicted that Kireh would make this mistake... drop that thought; she's not supposed to speculate on Marra's predictions of her.) But Kireh is sad about wasting, say, the Green Gulliman, who does have a sense of Lawfulness.
Even if the outcome is positive, she still made a mistake by not thinking about it first. She already knew that overusing Marra's Inquisition damages petitioners! Normally, now is when she would find a superior to correct her: the main camp's regulator, one of her three semi-superior cantors, Marra Herself. But she's alone here. Marrans aren't supposed to be without a superior! Marra's choice to ascend and leave Herself unguided was a sacrifice. Kireh can patch the habits that led to this mistake, and maybe that's good enough, but it's still wrong.
- Kireh might not be alone here. She might find a superior, or another cantor for them to be each other's semi-superiors. Or she might train a cleric for Marra: a second-circle cleric as a semi-superior, or a third-circle cleric definitely above her.
She patches the error, but crudely so it's easy to reverse, and sets a reminder to consult a superior when she has one.