Hmm, probably FaQ material.
You won't get one. The spell is pretty clear. And so is Ultimate Intrigue:
The first thing to note is that at the lowest levels, alignment detection spells simply don’t register NPCs due to their low level. Other than clerics, undead, and evil outsiders, creatures require 5 Hit Dice or more to register with detect evil. The second thing to keep in mind is that creatures with actively evil, good, chaotic, and lawful intents register as that alignment if they have enough Hit Dice, regardless of their actual alignment. So a selfish merchant whose heart is moved by an orphan’s plight into an act of largesse would register as good at the time, and a loyal knight forced to kill an innocent child to stop a war could appear evil while she formulates and executes the deed. The final thing to consider is that alignment detection is exceptionally easy and cheap to foil in the long-term.