Training in Insight does not make you a human lie detector. Too often in D&D a PC rolls Insight and on a successful check knows immediately if a person is lying. This shouldn’t always be the case. Sometimes you need to work at it. If you’ve never met this person before how do you know that they’re lying. Everybody lies to some extent. Figuring out if the lie they just told you impacts your current line of questioning or not requires work.
For situations where more than one simple roll is required, a structured skill challenge may be more suitable. This is not to say that every attempt to detect a falsehood requires anything this complex, but it might be a good idea to remind the PCs that sifting through an intricate web of lies often takes time and many skill checks.
The setup provided below requires the PCs to interview many suspects. Most are innocent. Strong-arming or threatening them may not be such a good idea. Their actions during this investigation will have lasting consequences so they should proceed cautiously.
Creative PCs may opt to use rituals as part of their investigation. See Using Rituals In Skill Challenges, the section describing the Discern Lies ritual in particular.
- You are present at a large gathering or party when a crime is committed. A valuable item is stolen from a guest or someone is killed. You have no motive and are immediately cleared of the crime. Since you are impartial to the local politics, you are asked to interview the guests and determine who’s guilty.
- While travelling aboard a ship a valuable item is stolen or a passenger is killed. You have a rock solid alibi and are asked interviews the passengers and crew to determine who is guilty.
- Your reputation for order and honesty precedes you. After a prominent noble is killed you are asked to interview the suspects to determine if any are guilty.
Variable. Determine some key points that the PCs need to discover before they can draw a reasonable conclusion (even if it’s not the right one). Let them continue asking questions and interviewing people until they want to stop. For each clue uncovered count it as a success. Add up the successes and award XP appropriate to a skill challenge that would normally require that many successes. If the PCs accumulate 3 failures then they fail the skill challenge. On the third failure provide overwhelming (and false) proof that atruely innocent person is guilty.
Variable. If the PCs know the people they are interviewing, are from this town, city or province, or have a reputation in these parts (good or bad) then the level shouldn’t exceed that of the PCs. If the PCs are new in town then the level should be at least 2+ levels above the PCs.
Bluff, Diplomacy, Heal, History, Insight, Intimidate, Perception, Religion, Streetwise
PCs are likely to use Insight and Perception more than any other skills during this skill challenge. It’s important for the DM to ensure that these skills are not used interchangeably. A successful Perception check might let the PC notice a nervous “tell” during an interview, but Insight is required to understand its meaning. Perception should only reveal absolutes: A person fidgeted, stuttered, scratched their left ear, or looked down and away. Understanding what these clues mean requires Insight.
Bluff (moderate DC)
Claim to know facts that you really do not.
Bluff (hard DC)
Use your glib tongue and fast-talking to confuse the subject.
Diplomacy (moderate DC)
Sympathize with the subjects. Earn their trust through kind words.
Heal (hard DC)
Convince the subject that repressing painful memories is harmful. If they tell the truth they will feel better.
History or Religion (moderate DC)
Convince the subject to do the right thing and tell the truth. Use your knowledge of their sense of duty and honour, societal laws or religious beliefs to earn their trust.
Insight (moderate DC, assist)
Sometimes instinct is more accurate than logic. Trust your gut.
Insight (hard DC)
Interpret body language or other unusual behaviour observed during the interview.
Intimidate (hard DC)
Use threats in an attempt to extract information.
Perception (hard DC)
Listen for auditory clues, changes in inflection or unusual language.
Perception (moderate DC)
Watch for subtle clues when you’re conducting your interviews including facial expressions and body language.
Streetwise (easy DC, assist)
Ask around and learn more about the subjects before interviewing them.
After asking the right questions, corroborating the stories and weighing the evidence, the PC make an accusation that they believe is correct. If they’ve successfully completed the skill challenge then their decision is likely to stand up to the proper authorities.
The PCs were so quick to jump to conclusions that they accused the wrong person of committing the crime. If the wrongly accused can prove their innocence quickly enough perhaps the PCs will continue investigating and try to find the truly guilty.