You would have noticed. It's subtle but not extremely subtle, and you were literally standing between them.

Perhaps a different spell. Silent Telepathy is assuredly out of her reach, but a skilled wizard knows how to improvise. The point is that she organized… all of this, most likely. Gwen needed an accomplice to stand there and count while she gradually turned you into a chromatic clown, he complied after she showed him the commission, you assented because saying 'no thanks' when offered an exorcism is idiotic. The goal is obvious.

It takes another full minute of abracadabras and color-changes before Gwen finally relents. The count remains accurate the entire time. Her partner sits stock-still, staring into space. There's only one thing left to do, and while she doesn't particularly want to use up one of her precious third-circle spells she was at least able to put herself in a position where it was absolutely necessary. It's the optimal play, she consoles herself.

"Delu solisar."

Protection from Evil winks out like a dead firefly, quickly and without protest.

That's— that's it then. She took a hard swing at reality while its back was turned and reality didn't so much as flinch. Unless something extraordinary is going on, there is no deception here.

With an effort of will she relinquishes the death grip on her weapon and slouches back in her chair. Being vigilant against phantom threats is exhausting. A cup of tea would hit the spot, right around now.

"Is that the punchline?" she says icily.

"Hm? I'd call it good news. There was no—"

"Is that so? You spent all that time investigating me with a spell for doing the laundry and found nothing? I'm shocked."

"The point was to rule out—"

"Please, tell me what the point is! Tell me why I look like I was hugged by a flail snail! I thought painting my face bright red was some kind of mordant joke; it's such a relief to know that this was all an obligatory part of the sacred rite."

The implication of this is so stupid that it takes Gwen a moment to process and respond.

"I am not hazing you," she says slowly. "There is no one else watching us. I did not compel you to come here nor do anything else. I could not possibly have erased your entire—"

"That is a bold claim coming from a wizard, especially—"

"What? Who do you think I am, that I can just use up a – a Limited Wish on harassing someone I've never met before? I'm not a seventh-circle wizard!"

"Hogwash, you talked to him without words. Silent Telepathy is a seventh circle spell, which you didn't use, because wizards can do anything if they prepare for it. Undetectable mind-wipes are at most fourth-circle magic. Speaking of," she says to the cleric, "I am so terribly sorry that Gwen roped you into this interdepartmental feud. I assure you, her conduct is not representative of our values."

"An apology from a cop? Now I've seen everything." He laughs wheezily. "This skulduggery is for your benefit, chucklehead. Easier to break through an illusion than to run ahead with the next one; all you have to do is keep digging and the lies fall apart. That or they shoot you when you get too close to the truth, ha ha."