
How to detect lies with a storytelling technique - jessaustin
http://www.anecdote.com/2015/05/how-to-detect-lies/
======
mankyd
Read a book on this and this seems to corroborate much of what I read. One of
the most interesting and simple techniques discussed was the order in which
people recounted their stories.

The example given is an employee who is consistently late for work. If you ask
them to recount why they are late one day, a liar will tell you the story
linearly: "I woke up, ate breakfast, hopped in the car, was on my way, minding
my own business, then someone hit my car. I got out to trade insurance ...
[etc]".

A truth teller jumps around, usually starting with the climax "Someone hit my
car on the way in. I then realized my insurance was expired. I had just been
going through my bills the previous night ...".

This is easily ascribed to the fact that the liar is either making the story
up as they go or are repeating a rehearsed lie. A truthful person can jump
around easily because they are recounting distinct memories.

~~~
caminante
_> This is easily ascribed to the fact that the liar is either making the
story up as they go or are repeating a rehearsed lie. A truthful person can
jump around easily because they are recounting distinct memories._

Alternatively, the liar's experienced, good at his craft, and more capable of
jumping around.

~~~
iamsohungry
The best liars use the exhonerative voice to avoid telling a story about
themselves at all:

"Bags are subject to search" means "We will search your bags". "A shooting
involving Tacoma County Police left two suspects dead" means "Tacoma County
Police shot two suspects."

~~~
danso
Huh? I'm not disputing that institutions carefully use the passive voice to
clean their prose of negative connotations...but the two examples you mention
are not "lies"

1\. I've seen the "bags are subject to search" phrase many times, including
the public library. I cannot remember the last time my bag was searched, even
at the airport when the search is differentiated from the usual scan. So that
phrase is definitely not a cover-up for "We _will_ "

2\. Again, not a lie. And I don't mean in the "not _technically_ a lie". There
are many cases where there is a shootout involving police and the cause of the
suspect's death is ultimately determined as suicide. So the "A shooting
involving..." phrase is perfectly acceptable in a breaking news update when no
determination has yet been made.

~~~
iamsohungry
> I'm not disputing that institutions carefully use the passive voice to clean
> their prose of negative connotations...but the two examples you mention are
> not "lies"

Clippy says: "Hey, it looks like you're trying to start a semantic argument!
Can I help with that?"

> I've seen the "bags are subject to search" phrase many times, including the
> public library. I cannot remember the last time my bag was searched, even at
> the airport when the search is differentiated from the usual scan. So that
> phrase is definitely not a cover-up for "We will"

Congratulations on being middle class and white.

> There are many cases where there is a shootout involving police and the
> cause of the suspect's death is ultimately determined as suicide. So the "A
> shooting involving..." phrase is perfectly acceptable in a breaking news
> update when no determination has yet been made.

There are many cases where this isn't the case, too.

~~~
danso
Actually, I'm Asian, FWIW.

------
throw7
Well, at an airport security check I got interviewed before boarding and the
guy asked me how I got here. I thought it was a weird question to ask and I
answered I got here by airplane (I was in a foreign country visiting).

He was totally non-plussed by the answer and said, "No, how did you get
_here_?"... I was actually confused by the way he said it and he added, "What
did you do this morning to get _HERE_?". I said I got up, packed, got on the
train, transferred to the airport bus, and got here. He just paused and moved
on to a few innocuous questions. It was kind of comical. I was waiting to be
led to some back room for further interrogation, but in the end he just said
'enjoy your trip". :)

~~~
pbhjpbhj
Probably the point of the question was to be confusing: it strikes me that if
you give the brain something to work on - parsing and responding to a
confusing question - it could make responding with false information more
difficult.

Imagine you were trying to remember the details of a false passport and an
alibi for what you'd be doing - you get a weird question and your brain is
then suddenly blank when you try to present your false identity.

Seems plausible?

~~~
freshhawk
Seems likely, also simply as a gauge to how you act while confused. A nervous
person will probably be confused in a noticeably different way.

They tell bad jokes to see how much you laugh, suddenly put on annoyed or
aggressive personas to see how you react to those, etc.

But your point about interrupting a liars narrative makes a lot of sense as
well.

------
alexggordon
First off, I think this technique is completely true, in my own experience.
However, I think this isn't the end-all lie detector, in that you have to know
what to have the subject tell a story about.

Take the issue of national security (in the USA). To get a national security
job, you'll have to go through a lie detector test[0], where they'll ask you a
ton of questions. Say I'm lying about my name. Do you ask a story about my
name? Say you ask about my childhood instead. If I was lying about my
childhood, I'd tell stories that were as closely aligned with real life as
possible, and change as few details as I needed to. A story about playing in
the park in the summer with my parents doesn't change a whole lot if it's in
North America or Europe.

Bottom line is, I think this method works, with the caveat that you have to
know the event or thing that they would be lying about. Trying to find out if
a spouse killed their significant other? Check, you can ask the stories around
their alibi. Trying to figure out if James Bond is going to sell national
secrets? What story are you going to ask about?

[0] [http://federalnewsradio.com/federal-drive/2012/12/what-
feder...](http://federalnewsradio.com/federal-drive/2012/12/what-federal-
applicants-should-know-about-polygraph-tests/)

~~~
AnthonyMouse
> Bottom line is, I think this method works, with the caveat that you have to
> know the event or thing that they would be lying about.

You also have to be careful in the other direction. False negatives are a
problem but false positives are an even bigger problem because most people
will be innocent. And you could be asking someone to recall a time when they
were drunk or exhausted or under stress, or the truth is embarrassing or
painful to think about, or the day you're asking about was entirely
unremarkable, etc.

------
dang
I thought this had been discussed on HN earlier this year, but searching for
it has failed me. I did find
[https://news.ycombinator.com/item?id=9061964](https://news.ycombinator.com/item?id=9061964),
though, which looks interesting and related and got no attention.

Edit: I found it:
[https://news.ycombinator.com/item?id=10180728](https://news.ycombinator.com/item?id=10180728).
Interesting and related and got lots of attention. But not a duplicate.

------
iamleppert
These kinds of analytical methods (i.e. word counting) work well in controlled
experiments when you know you're going to be lied to by a subject, and also
told the truth so you have a point of reference.

In the real world, you don't know _if_ you're being lied to. That's the entire
point! You don't have any normalized data that says this is the number of
words a person uses when they're telling the truth and when not, so the
detection technique will be as inaccurate as this missing calibration info.
And since there are wide variances between individuals in both general memory,
recall, and "talkativeness" you have to develop a sample corpus per person.
Also you need to interview the person on multiple days and randomize when you
ask the questions so as not to introduce bias and to protect from ordering.

It's easy to conduct a study like this and proclaim an obvious conclusion, but
this means almost nothing for real-world application of the technique.

~~~
babo
It works if the interviewer is unaware of the situation.

------
barce
This is seriously flawed for folks that suffer memory degradation under
stress. tl;dr: the guy with amnesia is the liar.

~~~
cryoshon
Yeah. There's a reason why the standing order for the public is "don't ever
talk to the police without your lawyer in the room". Doubt or confusion about
past events is often perceived as an attempt to fabricate. Add in the ability
for the interviewer to feed false facts to you in an attempt to question your
story, and it's tough to pass the truth as the truth.

It doesn't matter if you're actually innocent, what matters is whether they
can cast doubt on your innocence. Do you think you could repeat a simple story
that just happened to you recently in multiple different chronological and
detail configurations/contexts without introducing some inconsistencies?

------
jasode
_> Morgan found that the use of these mnemonic props – open-ended questions
about various sensations and sequences of events – dramatically increased
memory recall about what had happened. The subject’s stories consequently
became more and more complex, and richer in detail. Or at least, they did when
people were telling the truth. When it came to the lies, even well-rehearsed
ones, the subjects tended to falter and were unable to complete the interview.
According to Morgan, this was because when they were prompted to dredge up
deeper memories, the liars had nothing to draw on. _

Is this technique robust enough to detect implanted false memories
(psychologist implants memories of child molestation) or are such recalled
"memories" indistinguishable from real ones?

~~~
yasth
In an expansion[1](pdf) the classical Bugs Bunny at Disney study[2](pdf), over
several leading interviews participants added more and more detail. So while
it would probably work with an accidentally and freshly implanted memory; it
could probably be defeated by either purposely pushing for sense recall, or
perhaps accidentally over the course of many attempts to fix the "memory".

Knowing the technique is probably half way to defeating it in all honesty, as
long as a person has time to prepare (or be prepared).

[1][http://eprints.port.ac.uk/11286/1/filetodownload,62616,en.pd...](http://eprints.port.ac.uk/11286/1/filetodownload,62616,en.pdf)

[2]
[https://webfiles.uci.edu/eloftus/BraunPsychMarket02.pdfhttps...](https://webfiles.uci.edu/eloftus/BraunPsychMarket02.pdfhttps://webfiles.uci.edu/eloftus/LoftusLearning%26MemoryMisinfo05.pdf)

------
JackFr
This matches my experience that the best lies are based in truth and
experience. That is, either use something which actually happened to you and
change only the most necessary bits or use something which you know well to
have happened, just not necessarily to you.

------
jacinda
I wonder if successful con artists (or novel writers) have such a vivid
imagination that they would be able to pass this kind of test. If you have
such a good imagination that you can convince yourself you actually are in a
make-believe world, does the lie become just as convincing as the truth?

Put another way, if a novel is so richly detailed that I feel as though I'm
actually in the story, would describing my experience of that novel be
interpreted by this system as truth or a lie?

~~~
fjolthor
I'd think it depends on the amount of time you've spent imagining this
experience in the novel. If you have had enough time to vividly imagine the
entire experience, none of the questions should catch you by surprise and you
could answer almost as if you were actually there.

Regarding con-artists, yes I suppose it comes down to whether they can be as
quickly imaginative on the spot as most people who are truthfully recalling an
experience. That's probably where the inaccurate 15% of results come in.

------
swang
Wonder if there's a dataset for this. Maybe run a simple n-gram over the
interviews and see if certain phrases show up more often for truth tellers vs
liars.

If you're in the poker world, you know that physical tells _are_ a thing but
only to reaffirm your read and should not be the entire basis of whether you
bet/call/fold (ala Casino Royale).

Because it's so hard to place your entire reasoning because, "he's covering
his mouth, so he's bluffing" and "he's shaking his hands, he must have a good
hand" sometimes those are true tells, but sometimes maybe the room is just
really cold and the player is trying to warm himself up. Or maybe he's
throwing a reverse tell.

I remember Phil Hellmuth shilled a book about physical tells from a former FBI
agent, not sure if there was any substance to that book.

~~~
divs1210
That'd be great! Does anyone know if the data is available online?

------
api
Interesting how this dovetails with the art of writing -- when you're writing
a book, it makes the story much more compelling if you engage all five senses.
I wonder if we have some intuition about this and a story that doesn't feels
"one dimensional."

I also recall hearing a funny thing on a podcast once about someone
interviewing someone with a (pretty dubious even by weird paranormal stuff
standards) far-out alien abduction tale. They stopped them and asked "so you
were on this ship for hours... how did you go to the bathroom?" Interview was
over. They didn't have that one scripted. Turns out the person was actually
trying to virally market a book.

------
dbbolton
This method sort of reminds me of one of the opening scenes from _Das Leben
der Anderen_ (which is a great movie):
[https://www.youtube.com/watch?v=nkRxvEjprBM](https://www.youtube.com/watch?v=nkRxvEjprBM)

~~~
agumonkey
I remembered those tricks but not the movie it came from. How true is this
though ? even innocent people cracks down under pressure even if they rebel
against injustice at first. The amount of "intelligence" and organization to
protect whatever dogma a government wants to protects scared me. Noticed the
check mark when the student asked for a little humanity.

~~~
dbbolton
>How true is this though ?

Which part?

Honestly, I don't know how effective monitoring affect is per se but as a wild
guess I'd say it's at least as accurate as a polygraph/coin flip.

However, I think there is more weight in the idea that a story that is
repeated verbatim like that is more likely to be fabricated or at least
neglecting some of the truth (which is the takeaway I got from the article).

Sleep deprivation appears to be a pretty popular "enhanced interrogation
technique":
[https://en.wikipedia.org/wiki/Sleep_deprivation#Interrogatio...](https://en.wikipedia.org/wiki/Sleep_deprivation#Interrogation)

But just like every other form of torture its efficacy is highly questionable
(e.g. the inherent possibility of false confessions). I think sleep
deprivation is particularly problematic because while it does seem to almost
universally deplete the victim's willpower/resistance, it also causes a
profound detriment to memory and other cognitive function-- meaning it is
completely useless in cases where the victim isn't talking because they don't
remember the information rather than because they just don't want to
cooperate.

See "Educing Information, Interrogation: Science and Art, Foundations for the
Future":
[https://fas.org/irp/dni/educing.pdf](https://fas.org/irp/dni/educing.pdf)

~~~
rokhayakebe
_But just like every other form of torture its efficacy is highly
questionable_

This one truly baffles me. Man, as soon as I find myself tied on a chair, I
would spill the whole bag of beans and more. Heaven forbids they pull out the
pliers.

~~~
dbbolton
It shouldn't be baffling if you looked at the examples or study I posted,
because the point definitely wasn't "torture doesn't get people to talk".

~~~
rokhayakebe
I did not look into the links. I wasn't dis/agreeing, though, just saying
something related to your comment.

------
urlgrey
It's interesting that a low occurrence of unique words in a story can be an
indication of a lie. Does that position people speaking a secondary language
in an unavoidable place of distrust? Beyond body language, it's just more
difficult to tell if someone's story lacks richness because they're not
telling the truth, or they're simply not comfortable with the language and
have a small vocabulary to draw upon.

~~~
jessaustin
I think ideally you'd compare the story you're investigating with other,
provably-truthful stories told by the secondary-language speaker. That way
word reuse could be a relative value rather than an absolute one.

------
YeGoblynQueenne
I think I see a very obvious problem with this: in the experiment they ran,
the interviewer seems to be leading the interviewee in how to remember an
episode. Which means there is no way to make sure the interviewer is not
(consciously or not) planting those very same "rich details" that purportedly
make the difference between a lie and a truth, into the interviewee's
narration.

So I don't see that they're avoiding a "Clever Hans" situation at all. They
could be leading their interviewees on, providing subtle clues to the ones
that are telling the truth, but not to the ones that are lying.

And even if this was double-blinded, there's still no way to ensure the
interviewer doesn't interact in a different way with different interviewees,
therefore messing up the results of any experiment pretty badly.

------
Theodores
Nothing new here, this interviewing technique by storytelling has been
standard procedure for a long time with the British Police. One simple
variation is to recall the story from the beginning, then recall from the end
and see what doesn't match up.

~~~
mrestko
I used a variation of this trick when I was a resident assistant in college.
We had the unfortunate job of busting drinking parties in the dorms and part
of our responsibility was to collect ID numbers or social security numbers if
the person claimed to not have their IDs. People would quite happily rattle-
off a fake SSN. But if you wait 60 seconds and come back to them and ask for
the number in reverse, it's essentially impossible to repeat the same fake,
especially if you've been drinking.

~~~
pavel_lishin
I would have a hard time doing this with mine, and I'm sober.

Would people memorize fakes to give away consistently, or would they just
rattle off a random nine digit number?

~~~
at-fates-hands
Sometimes.

I used to be a bouncer in my college town and you'd be surprised at what
lengths kids will go to pass off their fake ID's as real. they'll memorize
everything on the ID, including where the city is located - "So Flagstaff, is
that North or South of Phoenix? I can never remember?"

I would ask for all the information on the ID if I thought they looked young.
Then once the person was confident they had passed my tests, I'd ask them what
their area code was when they call home. 9/10 a fake ID holder will fail this
test because its not something on the ID, but something they should know
without fail.

~~~
pavel_lishin
That's a pretty good idea! But doesn't this rather depend on you knowing the
area code yourself?

~~~
knodi123
Haha, either that, or pretending you do. You're only looking for people who
are not confident.

~~~
pavel_lishin
As someone who frequently forgets how old he is, I'd be kind of irked if
someone denied me entry because I said "I'm 28. No, wait, shit, 29!"

~~~
scott_s
Knowing some bouncers and bar tenders, they tend to have a dynamic level of
skepticism. If you look 25-ish, that sort of slip probably won't deny you
entry. If you look 20-ish, it may be more likely.

The difficulty here is that the incentives heavily favor allowing false
negatives, and denying false positives. I know that in Virginia, the bar
tenders were personally responsible if they served alcohol to anyone underage.
And in a college town (where I was for quite some time in grad school), there
are loads of underage kids trying to get into the bars, _and_ the authorities
would sometimes hire underage kids to test the bars.

~~~
pavel_lishin
Oh yeah, I definitely don't blame them, and I understand the incentive
structure. I don't even think that I necessarily disagree with it, given our
laws about drinking. It's just an irk :p

------
learc83
Hmm... My guess is that in a few years, we'll see the word frequency analysis
being used by police as an investigative technique.

However just like with drug dogs, they'll ignore the high false positives and
low prior probabilities.

~~~
redler
_Hmm... My guess is that in a few years, we 'll see the word frequency
analysis being used by police as an investigative technique._

It's an interesting thought. Imagine the linguistic equivalent of using
Benford's Law to detect accounting fraud.

------
djkz
This reminds me of Jobs To Be Done
([http://jobstobedone.org/](http://jobstobedone.org/)) interviews style that
dig into emotions of why customer switched to a different product.

The interview jumps around the story looking for any events that moved
customer to or from new solution, and digs into the emotions associated with
each event to get customers to recall all details.

------
thehoff
Slightly off topic, decided to check out the source (Criminal podcast) and
seems like a great one (based on the first two episodes). Subscribed.

------
jacquesm
That's a nice write-up but I think that experienced and well prepared liars
would be able to beat that.

The best way I've found to detect lies is that truth is 'internally
consistent' and lies never are, all you need to do is to focus on any
inconsistencies not matter how small and then to apply pressure on them,
they'll fracture the story much like a crystal with a flaw in it.

~~~
betenoire
Considering that 'truth' is really our best recollection of past events, why
do you say that truth is internally consistent? I mean, maybe it is, but it's
not a given.

~~~
jacquesm
Truth is grounded in verifiable facts. You can be mistaken about facts, so
that's easy enough to fix. Liars can't change their story because once they do
the whole thing starts coming down, they can only keep so much of the
fabricated universe in their head.

That's mostly my interpretation of it, I've met only very few people that were
lying outright during the course of many DDs but when they do that's how they
all - so far, and of course there could be undetected ones that made it
through somehow though I highly doubt that - fell down.

From what I've seen it is _very_ hard to keep the story straight over the
course of a couple of weeks if it isn't true.

~~~
betenoire
> From what I've seen it is very hard to keep the story straight over the
> course of a couple of weeks if it isn't true.

Yes. I would add that it can be very hard to keep the story straight over the
course of a couple weeks EVEN IF IT'S TRUE. That's what I was trying to say.

~~~
jacquesm
Sure but the teller then has no vested interest in keeping the facts and the
story from deviating from each other whereas a liar does have that interest.
So the liar can't 'fix' the story but the person that tries to be truthful has
no problem.

------
teabee89
How does this work on truth-telling people under lot of stress, or fear?

------
davesque
Fun read. The technique they're describing here is the same one that attorneys
use during cross-examination of witnesses.

------
misiti3780
I worked with the DHS a few years back on a project trying to use ML to detect
lies based on a variety of ques, including paul ekman's research into facial
expressions:

[https://en.wikipedia.org/wiki/Project_Hostile_Intent](https://en.wikipedia.org/wiki/Project_Hostile_Intent)

------
andrewclunn
Sounds to me like some of these people just aren't good liars.

~~~
veb
Yeah, I know right? I'm sure I read on HN some time earlier that CIA agents /
undercover would always make sure their lie is actually as close to the truth
as possible -- if it comes down to it. (last resort type thing).

I could do this easy peasy, and then ask me to do it backwards and I'll stare
at you and go "No idea, I'd have to think about it... generally don't think
backwards".

The key in any case, is always... don't give them rope. Patience.

------
empath75
What if the lie is just a minor detail embedded in an otherwise true story,
though?

------
imacomputer2
"The polygraph, for example, which measures physiological changes such as
blood pressure, respiration and skin conductivity, only achieves an accuracy
level of around 50%..."

Where does that statistic come from? I've definitely read that polygraphs have
over 90% success as long as you account for obvious "counter measures".
Basically, the person administering the test can clearly see if you are
pulling tricks to defeat it.

~~~
srean
If you could point me to such a document would appreciate it. Curious to know
if that is true.

------
anentropic
My first thought was a motivated liar could learn to beat it... surely part of
its success is from the liar being unprepared for the novel questioning
technique?

------
NickHaflinger
"When it came to the lies, even well-rehearsed ones, the subjects tended to
falter .. the liars had nothing to draw on"

How do you explain this man ..

[https://www.youtube.com/watch?v=-ucJN8cRDqM](https://www.youtube.com/watch?v=-ucJN8cRDqM)

------
mikepmalai
Storytelling is a very effective way to interview job candidates. It's a good
way to tear down inflated candidates to get to the truth, but more importantly
it's a good way to uncover and find talented high potential people.

------
buzzdenver
This might be a better technique if the suspect does not know what the
psychologist is looking for, but probably still does not work if he does. So
ultimately it still isn't very usable in the real world.

------
oldmanjay
To go along with enhanced interrogation, let's name this technique HD
questioning.

