Discern Lies

(Player's Handbook v.3.5, p. 221)

Level: Paladin 3, Vassal of Bahamut 3, Cleric 4, Knight of the Chalice 4, Savant 4 (Divine), Tyranny 3, Inquisition 4, Mechanus 4, Drow 4, Mind 4, Nobility 4,
Components: V, S, DF,
Casting Time: 1 standard action
Range: Close (25 ft. + 5 ft./2 levels)
Target: One creature/level, no two of which can be more than 30 ft. apart
Duration: Concentration, up to 1 round/level
Saving Throw: Will negates
Spell Resistance: No

Each round, you concentrate on one subject, who must be within range.
You know if the subject deliberately and knowingly speaks a lie by discerning disturbances in its aura caused by lying.
The spell does not reveal the truth, uncover unintentional inaccuracies, or necessarily reveal evasions.
Each round, you may concentrate on a different subject.