Should Insight be able to determine if an NPC is lying?

Should Insight be able to determine if an NPC is lying?

  • Yes

    Votes: 82 84.5%
  • No

    Votes: 11 11.3%
  • I reject your reality and substitute my own.

    Votes: 4 4.1%

  • Total voters
    97
Yes, it's possibly the most obvious reason for Insight to be in the game.

When someone IS lying, normally they roll Deception. You roll Insight against, and typically you only need to provide 2 outcomes: detect the lie or not (standard DM's answer: "he seems to tell the truth"). You don't really need an intermediate outcome like "you are not sure", because even when you tell the player there is no lie, the players won't be sure. The lower their roll, the less confident they will be, but they cannot assume anything.

When the NPC is NOT lying, you want to make it look the same so that the players may still be in doubt if they roll poorly, so IMO it's actually a good idea to make them still roll even if success is automatic ( since the NPC is not rolling Deception).

For added drama, a DM may also want to have a possible "false reading" outcome when there is no lie, i.e. have a chance that Insight results in "lies!" when there aren't any. If you want this option, my suggestion is NOT to tie this to a low roll (e.g. a natural 1), because that will give it away. Instead, pick a random number each time e.g. 14, so that if they roll a natural 14 then you tell them there is a lie when there actually isn't. You may find that mid-high numbers (10-15) work best for this :)

All these assume you want to let your players roll Insight in the open. If you roll for them and hide the result, you don't need any special idea.
 

Elfcrusher

Adventurer
Short answer: Yes, with a ‘but.’
Long answer: No, with an ‘except.’
This is really the best post in the thread.

Should Insight be useful in improving your odds of guessing correctly whether somebody is lying? Or giving you a hint of actions you could take to find out for sure? Sure.

Should a single Insight roll give you a 100% accurate, binary (true/false) lie-detector reading? No, I don't think so.
 

77IM

Explorer!!!
Should a dagger be able to kill an NPC?

(X) Yes
( ) No
( ) Lemon cupcakes

-----

Except...
Sometimes, when you hit an NPC with a dagger, they don't die!
Sometimes, when you miss an NPC with a dagger, they die anyway, a round or two later!
Sometimes, you can kill an NPC using something that isn't a dagger at all!
Sometimes, you can use a dagger to skin a rabbit, or cut slices of lemon meringue pie!
Sometimes, an NPC can use a dagger to kill YOU!
 

DEFCON 1

Legend
The fun part for me as a DM is when someone asks to roll Insight and rolls poorly... I just decide in the moment whatever I wish to say. Sometimes it's "You can't tell"... sometimes it's "You are dead certain they are lying"... sometimes it's "You think they are telling the truth, but something doesn't feel right"... or whatever I want. And sometimes *I'M* lying about what info I'm giving them and sometimes I'm telling the truth.

Nothing messes with my player's heads more than when they roll a '3' on Insight and I tell them "Oh yeah, this person is 100% lying to you"... and the truth is the NPC *is* lying to them. Because they automatically think that their bad roll means the exact opposite of what I've told them. When in truth their bad roll means they have no concrete information to hang their hat on, so nothing I say should be taken at face value because nothing their PC "notices" should be either.

It's like in poker... if you bluff, you occasionally need to be caught doing it so that your opponents can never know in the future whether you are or not.
 

DM Dave1

Adventurer
Should a dagger be able to kill an NPC?

(X) Yes
( ) No
( ) Lemon cupcakes

-----

Except...
Sometimes, when you hit an NPC with a dagger, they don't die!
Sometimes, when you miss an NPC with a dagger, they die anyway, a round or two later!
Sometimes, you can kill an NPC using something that isn't a dagger at all!
Sometimes, you can use a dagger to skin a rabbit, or cut slices of lemon meringue pie!
Sometimes, an NPC can use a dagger to kill YOU!
This is a fun example which shows how flexible the game can be in practice. As much as our minds would like to simplify things into yes/no, pass/fail, or 1s/0s, it seems that a not-insignificant amount of the best fun awaits in the gray area in between.
 

Yardiff

Explorer
Should a dagger be able to kill an NPC?

(X) Yes
( ) No
( ) Lemon cupcakes

-----

Except...
Sometimes, when you hit an NPC with a dagger, they don't die!
Sometimes, when you miss an NPC with a dagger, they die anyway, a round or two later!
Sometimes, you can kill an NPC using something that isn't a dagger at all!
Sometimes, you can use a dagger to skin a rabbit, or cut slices of lemon meringue pie!
Sometimes, an NPC can use a dagger to kill YOU!
Hopefully your not doing this with the blood of the NPC you failed to kill still on it.
 
Last edited:
Yes, of course.

"Lying" is an attempt to deceive someone. An Insight check can give you an inkling whether or not an NPC is attempting to be deceitful.
 

Elfcrusher

Adventurer
Should a dagger be able to kill an NPC?

(X) Yes
( ) No
( ) Lemon cupcakes

-----

Except...
Sometimes, when you hit an NPC with a dagger, they don't die!
Sometimes, when you miss an NPC with a dagger, they die anyway, a round or two later!
Sometimes, you can kill an NPC using something that isn't a dagger at all!
Sometimes, you can use a dagger to skin a rabbit, or cut slices of lemon meringue pie!
Sometimes, an NPC can use a dagger to kill YOU!
I actually think this is a GREAT example because:

1) There are very explicit rules for how a dagger can be used to kill an NPC. Note that it's not not necessarily, "Roll one success, NPC dies" but it's one component: you roll to hit, then you roll some damage; wash/rinse/repeat and eventually it dies. Unless it has other counteractions it can take. And note that there are potentially negative consequences of trying this approach. (Surprise! He's a shapeshifted Dragon!)

2) As [MENTION=6776133]Bawylie[/MENTION] pointed out somewhere that if the PCs capture an NPC and hold a dagger to his throat, and for whatever reason they decide to kill him, it's also perfectly fine to narrate an insta-kill (possibly with some kind of die roll, although I'd probably let the player choose what sort...Medicine, straight Dexterity, etc., instead of an attack roll).

Similarly:

1) A successful Insight roll could be one component toward determining if an NPC is telling the truth. In some circumstances a single roll might even be sufficient. (That is, you figure out his Bond, at which point you figure it's highly likely that he is lying.) But there should be a consequence to trying and failing.

2) if a scene is properly set up so that the truth (or not) of the NPC can be determined by asking the right questions, looking for the right clues (including possibly spying on the NPC afterwards) then no Insight roll is needed.
 

Mort

Community Supporter
1) A successful Insight roll could be one component toward determining if an NPC is telling the truth. In some circumstances a single roll might even be sufficient. (That is, you figure out his Bond, at which point you figure it's highly likely that he is lying.) But there should be a consequence to trying and failing.
I fully agree here - though the consequence seems fairly apparent - you gain incorrect information as in:

1. You think the subject is lying when he isn't; or
2. you think he's telling the truth when he's lying; or
3. You get the wrong bond - as in "I will protect the king or die trying." when his real bond is "I will kill the king even if I have to die trying."

#3 of those (wrong bond) is likely to lead to some interesting places - so seems like a great thing to incorporate.

2) if a scene is properly set up so that the truth (or not) of the NPC can be determined by asking the right questions, looking for the right clues (including possibly spying on the NPC afterwards) then no Insight roll is needed.
This is true, as far as it goes, but tricky. The DM must be flexible enough to really go with player input and make sure reasonable goals and their methods of execution are met with reasonable levels of success.

Too often DMs have a set solution in mind (that seems obvious to them) and are strangely inflexible to accepting others - leading to massive frustration from the players.
 

Oofta

Title? I don't need no stinkin' title.
2) if a scene is properly set up so that the truth (or not) of the NPC can be determined by asking the right questions, looking for the right clues (including possibly spying on the NPC afterwards) then no Insight roll is needed.
Which is why I never give 100% guaranteed concrete responses. It's never "he's lying" it's "he seems to be hiding something" or "they seemed honestly surprised when you told them the cook was dead". Sometimes it's even "she's calm and unconcerned" which could be a tip-off that somethings wrong because they should be upset or an emotional wreck.

If I were a perfect actor and my players were as good at picking up verbal and non-verbal queues as their PCs are this wouldn't be necessary. But the reality is I won't communicate every twitch or hesitation and even if I did it would end up relying on the skill of the player, not the PC to pick up on the subtleties.

I rely quite a bit on passive insight when doing this.
 

ad_hoc

Adventurer
I said no because you don't use insight.

You perform an action and the DM determines the outcome which may involve making a Wisdom (insight) check.
 

Mort

Community Supporter
I said no because you don't use insight.

You perform an action and the DM determines the outcome which may involve making a Wisdom (insight) check.
Hmm - that's still using insight. Who determines whether the check is needed isn't actually relevant to the question.
 

Oofta

Title? I don't need no stinkin' title.
I just thought I'd throw in my 2 coppers on why I allow people to ask for insight, use passive insights or ask for checks with an example. As far as how we get to the point of relying on a PC skill instead of player skill, I really don't care. To me that's just a stylistic choice. My point is that I think skills like insight can be used to give a lot of hints and clues, it can add depth and richness to the game that doesn't rely on DM or player skills.

Scenario:
The group is questioning a suspect in a who-dunnit. Think typical police procedural with the cops interviewing the suspect, Franky Nine Fingers.
PC: "Where were you last night after dusk."
Franky: "I was at home as usual."
PC: "Any witnesses?"
Franky: "Nah, I live alone. Nobody but me."
PC: "So you know nothing about Jimmy the Nose dying?"
Franky: "Jimmy's dead? No I didn't know that"​

So short, but simple (the conversation would obviously continue). From the text, there's no possible way of knowing whether or not Franky is on the up-and-up. So let's add in some details you could pick up with insight. But let's say Franky has a decent deception skill and whether or not the PC should pick up on subtle details is not certain
PC: "Where were you last night after dusk."
Franky: "I was at home as usual." [he's being sarcastic and condescending]
PC: "Any witnesses?"
Franky: "Nah, I live alone. Nobody but me." [shift's a bit in his seat, this question makes him uncomfortable]
PC: "So you know nothing about Jimmy the Nose dying?"
Franky: "Jimmy's dead? No I didn't know that" [not really surprised]​

It's obvious our Franky boy is hiding something, questioning/actions ensue. He's probably now suspect #1.
PC: "Where were you last night after dusk."
Franky: "I was at home as usual." [he paused slightly after "at home", is he hiding something?]
PC: "Any witnesses?"
Franky: "Nah, I live alone. Nobody but me." [Franky glanced nervously at the captain of the guard. Why?]
PC: "So you know nothing about Jimmy the Nose dying?"
Franky: "Jimmy's dead? No I didn't know that" [Seems to be honestly surprised]​

What's going on? He may not be a primary suspect, but there's something fishy. Maybe the captain of the guard knows something? Maybe he visited Franky? Or maybe Franky is being 100% honest but suspects that someone is watching his house.

Or any number of other variations. Both of these scenarios are incredibly common fictional tropes. The point is that subtle queues may or may not be picked up. It shouldn't be up to the DM to act this out or the players to pick up on it because then it's not the PCs doing the questioning, it's the players. I am not my PC.
 
Last edited:

ad_hoc

Adventurer
Hmm - that's still using insight. Who determines whether the check is needed isn't actually relevant to the question.
The character doesn't use insight though.

They do a thing. Insight might be involved in resolving their action.

I'd be fine with passive insight to tell whether something isn't quite right, just like passive perception.

"I roll insight to tell if they are lying" goes against how 5e is designed.

1. There is no mechanism to stop the player from rolling until they get a 20 so you're essentially playing a game with everyone having passive insight scores of 20+ rather than 10+.
2. Rolls should be exciting and pivotal. Having the party make ability checks every time someone talks to them is not.
3. Players describe what their characters are doing in 5e. They don't declare that they are using X skill.
 

D1Tremere

Villager
Insight, as written, lets you attempt to determine the true intentions of a creature. If the creature is intending to lie to you, you can use insight to potentially determine this, likewise it will let you determine if they are intending to be honest with you. If they mislead or lie to you because of a mistake, then it is not their intention to do so, and a successful Insight check will let you know that they do not appear to be lying.
So it would seem that a successful insight check should let you know what the subject's intentions are, but those intentions may not lead to the truth if the subject is mistaken. Just because you think they are not attempting to deceive you does not mean they are telling the truth.
If a player fails their insight check I treat it much like a success. They believe the intentions of the subject are whatever the subject would want them to believe. If the subject is lying and a PC fails their roll then the PC is told that the subject does not appear to be intentionally misleading them.
 

Elfcrusher

Adventurer
I just thought I'd throw in my 2 coppers on why I allow people to ask for insight, use passive insights or ask for checks with an example. As far as how we get to the point of relying on a PC skill instead of player skill, I really don't care. To me that's just a stylistic choice. My point is that I think skills like insight can be used to give a lot of hints and clues, it can add depth and richness to the game that doesn't rely on DM or player skills.

Scenario:
The group is questioning a suspect in a who-dunnit. Think typical police procedural with the cops interviewing the suspect, Franky Nine Fingers.

PC: "Where were you last night after dusk."
Franky: "I was at home as usual."
PC: "Any witnesses?"
Franky: "Nah, I live alone. Nobody but me."
PC: "So you know nothing about Jimmy the Nose dying?"
Franky: "Jimmy's dead? No I didn't know that"​

So short, but simple (the conversation would obviously continue). From the text, there's no possible way of knowing whether or not Franky is on the up-and-up. So let's add in some details you could pick up with insight. But let's say Franky has a decent deception skill and whether or not the PC should pick up on subtle details is not certain

PC: "Where were you last night after dusk."
Franky: "I was at home as usual." [he's being sarcastic and condescending]
PC: "Any witnesses?"
Franky: "Nah, I live alone. Nobody but me." [shift's a bit in his seat, this question makes him uncomfortable]
PC: "So you know nothing about Jimmy the Nose dying?"
Franky: "Jimmy's dead? No I didn't know that" [not really surprised]​

It's obvious our Franky boy is hiding something, questioning/actions ensue. He's probably now suspect #1.

PC: "Where were you last night after dusk."
Franky: "I was at home as usual." [he paused slightly after "at home", is he hiding something?]
PC: "Any witnesses?"
Franky: "Nah, I live alone. Nobody but me." [Franky glanced nervously at the captain of the guard. Why?]
PC: "So you know nothing about Jimmy the Nose dying?"
Franky: "Jimmy's dead? No I didn't know that" [Seems to be honestly surprised]​

What's going on? He may not be a primary suspect, but there's something fishy. Maybe the captain of the guard knows something? Maybe he visited Franky? Or maybe Franky is be being 100% honest but suspects that someone is watching his house.

Or any number of other variations. Both of these scenarios are incredibly common fictional tropes. The point is that subtle queues may or may not be picked up. It shouldn't be up to the DM to act this out or the players to pick up on it because then it's not the PCs doing the questioning, it's the players. I am not my PC.
I very much agree with the part in bold, and I think it’s one reason it’s so hard to handle lying well in an RPG. So hard, that although I rail against using Insight as a binary lie detector test, I understand the appeal: all the other options are either really hard to do well (requiring either fast thinking or preparation time...or both) or they are generally transparent, nudge-nudge-wink-wink euphemisms for binary lie detection.

So, yeah, I get just wanting to avoid the whole thing with a simple, mechanical solution.
 

Mort

Community Supporter
The character doesn't use insight though.

They do a thing. Insight might be involved in resolving their action.
And can insight resolving the action result the PC sussing out a lie?

I'd be fine with passive insight to tell whether something isn't quite right, just like passive perception.
Ok

"I roll insight to tell if they are lying" goes against how 5e is designed.
But that wasn't the question.

1. There is no mechanism to stop the player from rolling until they get a 20 so you're essentially playing a game with everyone having passive insight scores of 20+ rather than 10+.
2. Rolls should be exciting and pivotal. Having the party make ability checks every time someone talks to them is not.
3. Players describe what their characters are doing in 5e. They don't declare that they are using X skill.
Again, it seems you're arguing about a different question than I am asking.

I'm not asking if the player gets to declare an insight check.

The question is does the insight skill (which exists, players can choose to be proficient in it, even) allow for telling if someone else is lying.
 
Last edited:

D1Tremere

Villager
The character doesn't use insight though.

They do a thing. Insight might be involved in resolving their action.

I'd be fine with passive insight to tell whether something isn't quite right, just like passive perception.

"I roll insight to tell if they are lying" goes against how 5e is designed.

1. There is no mechanism to stop the player from rolling until they get a 20 so you're essentially playing a game with everyone having passive insight scores of 20+ rather than 10+.
2. Rolls should be exciting and pivotal. Having the party make ability checks every time someone talks to them is not.
3. Players describe what their characters are doing in 5e. They don't declare that they are using X skill.
This isn't how I see it for whatever that is worth.
A player uses insight in one of two occasions, they are actively curious about a subjects intentions (such as questioning a subject), or a subject is actively attempting to deceive them (as a DM may call for an insight check if they think the PCs should have a chance of spotting a deception roll).
A player cannot roll until they get a 20 because they have no reason to. If they succeed then they are told some version of the subject intentions are true, and they are also told this if they fail. Either way, the character believes they have succeeded.
 

Advertisement

Top