Learn two simple questions that can help uncover inconsistencies in someone’s story, why contradictions may appear, and why no question can reliably prove that someone is lying.
Have you ever listened to someone’s story and felt that something didn’t quite add up?
When people tell stories from memory, their accounts can naturally contain gaps, changes in wording, or small inconsistencies. Sometimes those inconsistencies are meaningful—but they don’t automatically prove deception.
There is no foolproof psychological question that can identify every liar. However, asking open-ended questions and then revisiting important details later can sometimes reveal contradictions that deserve closer attention.
Question 1: “Can You Tell Me Exactly What Happened?”
Instead of immediately accusing someone of lying, ask them to explain the situation in their own words.
An open-ended question gives the person an opportunity to provide details without being guided toward a particular answer.
Pay attention to the content of the account, rather than simply watching their body language.
For example, you might notice:
- Important details are repeatedly avoided
- The sequence of events is unclear
- The person gives unusually vague answers
- Different parts of the story don’t fit together
But remember: nervousness, poor memory, stress, or confusion can also produce these behaviors.
Question 2: “Can You Walk Me Through What Happened Again, From the Beginning?”
After some time has passed, ask the person to explain the important events again.
The goal isn’t to pressure them into making a mistake. Instead, you’re looking for whether the central facts remain reasonably consistent.
A genuine memory can contain small variations because human memory isn’t a perfect recording. People may remember an event differently depending on what they noticed, how much time has passed, and how stressful the situation was.
A major contradiction in an important detail may warrant clarification, but it still isn’t automatic proof of lying.
Why Contradictions Can Be Interesting
When someone deliberately invents a story, maintaining consistency can require remembering details they created earlier.
If you return to the same subject from a different angle, discrepancies may sometimes become apparent.
For example:
First: “What did you do after work?”
Later: “You mentioned going straight home. What did you do when you got there?”
The second question encourages the person to reconstruct the timeline rather than simply repeat the original statement.
Don’t Rely on Body Language Alone
One of the biggest misconceptions about lie detection is that you can identify a liar by looking for a specific behavior.
Avoiding eye contact, fidgeting, touching the face, speaking quickly, or appearing nervous does not reliably prove deception.
People behave differently when they’re anxious, uncomfortable, shy, or under pressure—even when they’re telling the truth.
Likewise, someone who appears calm and confident isn’t necessarily being honest.
Look for Facts, Not “Liar Signals”
If you genuinely need to determine whether someone’s story is accurate, concentrate on information that can be independently checked.
Consider:
- What exactly is being claimed?
- Does the timeline make sense?
- Are important details consistent?
- Can relevant facts be verified?
- Is there an innocent explanation for the apparent contradiction?
This approach is much more reliable than trying to interpret a person’s facial expressions.
Give the Person a Chance to Explain
Before deciding that someone has lied, ask about the inconsistency directly.
For example:
“Earlier you said you arrived at 7, but now you said you arrived closer to 8. Can you help me understand the difference?”
There may be a perfectly reasonable explanation.
They might have misunderstood the original question, remembered the time incorrectly, or simply expressed themselves poorly.
The Important Limitation
No two-question technique can guarantee that you’ll “catch a liar.”
Professional investigators and psychologists also recognize that deception detection is difficult. Even trained observers can make mistakes when trying to determine whether someone is telling the truth.
The strongest approach is therefore to treat contradictions as questions to investigate, not proof of guilt.
Final Thoughts
If you want to understand whether someone’s story is reliable, ask open-ended questions, listen carefully, revisit important details, and compare the answers with independently verifiable information.
The most useful technique isn’t a magical pair of questions.
It’s curiosity without accusation, careful attention to facts, and a willingness to consider explanations other than deception.