[RPG] What are the limits of Glibness concerning Deception

dnd-5espells

I was reading the description of the the 8th-level spell Glibness the other day and its wording seemed to be pretty broad in scope. The specific passage I'm interested in is this:

Additionally, no matter what you say, magic that would determine if you are telling the truth indicates that you are being truthful.

That seems like a pretty powerful, absolute statement. It leads me to believe that the spell completely renders any attempts at interrogation by magic completely useless. On the other hand, despite that power, it seems to also indicate that a lucky Insight check can still detect lies just fine because an Insight check isn't considered magic. Are these conclusions correct? Consider the following situations.

  1. Let's say there are two Warlocks, Bob and Jim. Bob casts Glibness on himself, and Jim casts Detect Thoughts on Bob. Jim asks Bob a question to which he doesn't already know the answer. Bob lies. Can Jim tell Bob lied, or does Glibness beat Detect Thoughts because Jim is using magic to determine Bob's truthfulness?

  2. Same scenario. Two Warlocks, Bob and Jim. Bob casts Glibness on himself, and Jim asks Bob a question to which he doesn't already know the answer. Bob lies again. This time Jim casts Dominate Person on Bob and orders Bob to reveal whether or not he lied. He then orders Bob to answer his questions truthfully. Can Jim tell Bob lied, or does Glibness beat Dominate Person because Jim is using magic to determine Bob's truthfulness? Can Jim use Dominate Person to compel Bob to tell the truth despite the effects of Glibness?

  3. Same scenario. Two Warlocks, Bob and Jim. Bob casts Glibness on himself, and Jim asks Bob a question to which he doesn't already know the answer. Bob lies again. Despite rolling a 3 on his Deception check, Bob gets to act as though he rolled a 15 thanks to the effects of Glibness. Assuming his CHA modifier is at least a +3 and at most a +5, then Jim would ordinarily need to roll somewhere in the range of 18-20 on his opposing Insight check in order to determine Bob is lying. Assuming he succeeds, can he tell Bob is lying?

Best Answer

I believe you are correct on both counts. To answer your scenarios though:

  • Glibness definitely beats detect thoughts as it would be exactly the type of thing that the spell intends to prevent. The person with Glibness cast on them would read as having thoughts consistent with truthfulness.

  • I don't think Dominate Person here will work either. For similar reasons to why Detect Thoughts doesn't work. The person who has glibness cast on them at least in appearance to spell effects is completely truthful. Thus the dominated person's response would be that they were being truthful. I don't think that Dominate would work to compel the truth as again, as far as the magic is concerned the person is already convinced it's true.

  • Yes. I believe he would be able to. Since he is attempting to use a mundane means of defeating glibness it is subject *only to the opposed Deception check, and not the auto failure of magic.