Detect lie
From Ardrana
A priest who casts the detect lie spell is immediately able to determine if the subject creature deliberately and knowingly speaks a lie. It does not reveal the truth, uncover unintentional inaccuracies, or necessarily reveal evasions.
The spell's reverse, undetectable lie, prevents the magical detection of lies spoken by the creature for 24 hours.
Note: This version of detect lie originally appeared in the 2nd Edition Player's Handbook for Advanced Dungeons & Dragons from TSR. Its use here is for the purposes of providing context for the campaign only.