[0:00] (dramatic music)
[0:03] - A man has been found lying dead
[0:05] at the side of the road with oozing,
[0:07] elongated wounds to his back.
[0:09] To solve the murder,
[0:10] a local official calls all
the farmers in the village
[0:13] and demands they all bring
their tools to the main square.
[0:16] In the square, each man is
set to lay down his sickle.
[0:19] And then something
curious starts to happen.
[0:23] In the rising heat of the
morning, flies begin to descend,
[0:26] all landing on a single sickle.
[0:29] Its owner buckles,
[0:30] falling to his knees and admits to murder.
[0:36] This is from a 1247 book,
[0:38] "The Washing Away of Wrongs" by Song Ci.
[0:40] And it's the first writing we have
[0:42] of an empirical approach to forensics.
[0:44] But okay, big deal.
[0:46] Anyone could have just swapped the sickles
[0:47] or used their neighbor's.
[0:50] But forensics today are
much more accurate, right?
[0:54] Fingerprints support investigations
in over 70% of murders
[0:58] and DNA evidence in more than 90%.
[1:00] But then you also read an article like
[1:02] "Hair sample that put men
into prison for 28 years,
[1:06] turned out to be dog hair."
[1:07] - That is not science.
[1:09] That is not justice.
[1:10] - See, in 2009, the
National Academy of Sciences
[1:13] published this 350 page
report stating that,
[1:17] with the exception of
nuclear DNA analysis,
[1:19] no forensic method has
been rigorously shown
[1:22] to consistently demonstrate a connection
[1:24] between evidence and
a specific individual.
[1:26] And they also said that some tests
[1:28] do not meet the fundamental
requirements of science.
[1:31] So we ask people to rank five
famous forensic techniques,
[1:34] all of which are still
being used in court.
[1:38] Okay, five forensic techniques here.
[1:39] And I just need you to rank them in order
[1:41] of accuracy from the
least accurate down here
[1:43] to the most accurate.
[1:44] So what do you think?
[1:45] - I don't know if I'm gonna nail these.
[1:47] - Whoa. I dunno.
[1:48] - I don't know what
forensic to put first here.
[1:50] - Okay, hair. What are you thinking?
[1:52] - I think hair is last, eh?
[1:53] - I would probably put
the hair on the top two.
[1:57] - I feel like hair would
probably be the easiest to,
[2:00] - To fake?
- To fake, if you like.
[2:01] - I think hair at the bottom,
[2:04] because if it's not got
the follicle intact,
[2:05] just hair in general.
[2:07] - Mm.
- Do you think?
[2:08] - Yeah.
- Yeah.
[2:09] (dramatic music)
[2:11] - Hair has always been
an object of interest
[2:13] for crime scene investigators.
[2:15] And before DNA, they would look
[2:17] for the microscopic
similarities in the surface
[2:19] and the cross section of
hairs to try and get a match.
[2:22] For example, analyzing
how rough the fish scale
[2:25] like structure of the
surface of the hair is,
[2:27] or how the pigment is distributed
through the hair shaft.
[2:30] - [Announcer] The examiner's trained eye
[2:31] can learn many things.
[2:33] Is it human hair? Of what race?
[2:35] Animal hair? What family?
[2:37] This vital information may help
[2:39] to establish guilt or innocence
[2:41] - Between the 1970s and 1999,
[2:44] the FBI used this against
defendants in 268 cases.
[2:49] But when they later reexamined
this using DNA as evidence,
[2:52] it completely flipped
the field on its head,
[2:55] and it turned out that even
the most experienced FBI
[2:58] examiners would routinely
claim they had a match
[3:00] between hairs that were
from two different people.
[3:02] And they sometimes couldn't
even tell the difference
[3:04] between a human hair and a dog hair.
[3:07] (dog barking)
[3:08] Out of those 268 cases that
used microscopic hair analysis,
[3:12] 96% were declared false.
[3:15] 33 people were already sentenced to death,
[3:17] and nine were already executed
[3:19] by the time the errors were found.
[3:21] Today, the FBI only uses hair as evidence
[3:24] if it can be supported by DNA testing,
[3:26] which is why microscopic hair analysis
[3:28] goes to the bottom of this list.
[3:30] What do you think of bite marks?
[3:31] - On a crime scene?
- On a crime scene?
[3:32] - Yeah, yeah.
- It's been...
[3:33] Dracula, is Dracula there?
[3:34] - Least accurate is gonna be
[3:36] pretty close to bite marks, I think.
[3:38] - Midway.
[3:39] - Midway?
- Last.
[3:40] That's last.
[3:41] That's not realistic, innit?
- Okay. Okay.
[3:43] Mm.
[3:44] Bite marks at the top.
[3:45] The idea behind bite marks is simple.
[3:47] If you can use dental records
to identify a deceased person,
[3:50] surely you can identify a perpetrator
[3:52] by the bite marks left on a victim.
[3:54] Since the 1950s,
[3:55] bite mark analysis has been
used in thousands of cases.
[3:59] But then some experts, like
forensic dentist Mary Bush,
[4:02] started looking into
the method more deeply.
[4:05] - There was no scientific exploration
[4:08] into bite marks before they
were used in the court of law
[4:11] to say that this was even a feasible
[4:13] technique that you could do.
[4:15] - One study from the university at Buffalo
[4:17] used a set of model teeth to create
[4:19] 89 bite marks in cadavers,
[4:21] alongside controlled
bite marks made in wax.
[4:24] And out of those 89
bite marks made in skin,
[4:27] none of them matched the measurements
[4:28] of the ones made in wax or
the original model teeth.
[4:31] In fact, when they compared
the bite marks in skin
[4:34] to a wider collection of 411 model teeth,
[4:37] it wasn't even the original
model that made the bite mark
[4:40] that was the closest match.
[4:42] After 12 studies, their conclusion,
[4:45] bite mark transfer to
skin is not reliable.
[4:48] Skin isn't a good medium
[4:49] to leave an imprint of
someone's bite mark.
[4:51] It's soft, it's squishy, and
it distorts under pressure.
[4:54] But despite all this,
there's still been no ban
[4:57] and bite mark evidence is still
allowed in courts worldwide.
[5:00] We asked Dr. Bush for a comment
[5:02] and she said that while
the scientific method
[5:04] is happy to discard an
old and disproven theory,
[5:08] the justice system prefers consistency
[5:09] in a historical precedent.
[5:11] So even the new flurry
of evidence wasn't enough
[5:13] to get bite marks out of court.
[5:15] In fact, bite marks have
been used as evidence
[5:17] as recently as 2025,
[5:19] which is why it gets the
second worst spot on our list.
[5:23] Blood, if you don't have DNA
[5:24] and you're just using
like kind of the patterns
[5:26] that it leaves along the ground.
[5:27] How they splat.
- Right?
[5:28] - [Gregor] Like the picture,
[5:29] that blood on a crime
scene could give you.
[5:31] - Okay.
- I'm looking,
[5:32] thinking of putting blood at the end,
[5:33] but like, I don't know.
- Okay.
[5:34] Put blood at the end.
- Okay.
[5:35] - I would go blood then
[5:36] - Second.
- Second place.
[5:37] - Yeah, yeah, yeah, yeah.
[5:38] - So bloodstain pattern analysis.
[5:40] When someone is injured,
the way their blood pools
[5:43] and drips into the environment
is in a distinct pattern.
[5:45] And in 2020, "Wired"
actually did an episode
[5:48] with a crime scene analyst
[5:49] on how these different
stains can be interpreted.
[5:52] You can use physics and
biology to rewind the clock
[5:55] and extrapolate where in space
[5:57] the blood must have come from.
[5:59] This all started in 1971 when chemist,
[6:01] Herbert Leon MacDonell, published
[6:03] "Flight Characteristics and
Stain Patterns of Human Blood."
[6:06] In this book, MacDonell
described how you can use
[6:08] the width and length of a stain
[6:10] to calculate the angle of impact,
[6:12] and then using trigonometry,
[6:14] trace that back to the point
of origin of the spatter.
[6:18] The book quickly became the foundation
[6:20] of bloodstain pattern analysis,
[6:21] and everyone was using it.
[6:23] In fact, MacDonell even
established a Bloodstain Institute
[6:26] where thousands of US police
officers would enroll.
[6:29] The Supreme Court of Iowa
actually referred to the practice
[6:32] as relatively uncomplicated.
[6:34] So they didn't require
proof of its reliability.
[6:37] They were happy to go
ahead with MacDonell's tests
[6:39] that he did alone in his basement.
[6:42] And soon enough,
bloodstain pattern analysis
[6:44] was used in courts all over the states.
[6:48] But here's the problem.
[6:49] Plotting the flight
path of each bloodstain
[6:51] using trigonometry
assumes the trajectories
[6:53] were straight lines and gives
this common origin point,
[6:57] which suggests the victim was standing up.
[7:00] The issue is,
[7:01] MacDonell and then many forensic
investigators after him
[7:04] and even "Wired," failed to account
[7:05] for the effects of gravity and drag
[7:07] as obvious as this sounds.
[7:09] When you include these
in your calculations,
[7:11] the common origin point lowers,
[7:13] and you can see that in this example.
[7:14] It's more likely that the victim
was actually sitting down.
[7:18] The first study to measure
the baseline reliability
[7:21] of bloodstain pattern analysis
was only done in 2014.
[7:25] That's over 50 years
[7:27] after it started being admitted in court.
[7:29] And a large scale study from
2021 found that analysts
[7:32] come to different conclusions
about a way a stain was made,
[7:35] about 8% of the time.
[7:36] And that's because the same stain
[7:37] can come from many different mechanisms.
[7:39] And the fact that blood
differs from person to person,
[7:42] depending on how many red blood cells
[7:43] versus the plasma you have.
[7:45] Men actually tend to have
a 15% higher concentration
[7:48] of blood cells than women,
[7:50] which makes their blood more viscous.
[7:52] Nowadays, investigators have new software
[7:54] which uses fluid dynamics
[7:56] to help them map these complex 3D seams.
[7:58] So bloodstain pattern analysis
is improving in accuracy,
[8:02] which is why it gets this
middle spot in our list.
[8:04] Okay.
[8:05] But surely fingerprints
[8:07] must have a lot of
value in identification.
[8:09] How unique do you think fingerprints are?
[8:11] - I think they're pretty accurate.
[8:13] - They're fingerprints.
- Fingerprints.
[8:14] - That's probably one.
- That's number one.
[8:15] - Yeah.
- Okay. Okay.
[8:16] I mean, yeah, you use
fingerprints on your phone,
[8:18] you unlock it, you pay stuff, right?
[8:19] - 'Cause fingerprints are unique.
[8:21] Even when you have a passport,
[8:22] like they scan you when
you enter a country.
[8:25] - On March 11th, 2004,
[8:27] a terrorist organization
operating in Madrid
[8:29] set off explosions on
four commuter trains.
[8:32] The attack killed 193 people
and injured thousands more.
[8:37] Quickly after, the police
found a finger mark
[8:39] on a detonator bag left behind,
[8:41] and they matched it to Brandon Mayfield,
[8:43] a lawyer in Oregon.
[8:45] There's only one problem,
[8:47] there are no records of
Mayfield even leaving the US.
[8:50] He doesn't even own a passport.
[8:52] So how could he have pulled this off?
[8:55] - I honestly felt like I was being framed
[8:57] because I hadn't been outta
the country for over 10 years,
[9:00] - But despite that, the
fingerprint evidence against him
[9:02] was considered so damning that
Mayfield was incarcerated.
[9:06] But this wasn't a glitch.
[9:08] It was built into the
method from the start.
[9:10] (groovy music)
[9:12] In 1890s Kolkata,
[9:13] the city's rich career
criminals were avoiding jail
[9:15] by paying people to
serve sentences for them.
[9:18] It was a good tactic since, at the time,
[9:20] there was no practical
way to identify a person.
[9:23] So the criminals were
getting away with it.
[9:25] Three officers, Edward Henry, Azizul Haque
[9:27] and Hem Chandra Bose
[9:28] started taking the prints
[9:29] of everyone who came through the station,
[9:32] but they quickly ran into a problem.
[9:34] When they got a suspect in,
[9:37] how could they crosscheck their prints
[9:39] against their own database
[9:40] when there were 10 prints per person
[9:42] and thousands of people coming through?
[9:44] They needed a classification system.
[9:47] Haque proposed that they should look at
[9:49] whether a fingerprint has a whirl.
[9:51] It's the spiral pattern
[9:52] that a person might have on their fingers.
[9:54] And because each of your 10 digits
[9:56] can either have a whirl or not,
[9:59] there are a total of
two to the power of 10
[10:01] or 1024 ways your whirls can be arranged.
[10:05] So the officers just built
1024 wooden pigeonholes
[10:09] to organize these fingerprints.
[10:13] Okay.
[10:13] But what if like me,
you don't have a whirl?
[10:15] Well, two thirds of the
population actually don't.
[10:18] So the system had to go further.
[10:20] Once you have a pigeonhole number,
[10:21] you go for additional
layers of identification.
[10:24] Some of the additional categories
[10:25] that you could assign included
whether you had a plain arch,
[10:28] which was denoted with the letter A,
[10:30] or whether you had a tented arch,
[10:32] which was denoted with a T.
[10:34] Similarly, you could look at which side
[10:36] of the finger this loop structure is on.
[10:38] And with a few more
identifiers like these,
[10:41] we get a much more
in-depth classification,
[10:44] one that would go on to be
used for the next 100 years.
[10:48] Famously, the world's
first fingerprint bureau,
[10:51] which was established in London
in the New Scotland Yard,
[10:54] used this fingerprinting system.
[10:56] - I started in 1988
with Metropolitan Police
[10:59] in forensic services.
[11:01] - Could you paint a
picture of what the room
[11:04] would've looked like with
all these pigeonholes?
[11:06] How big was this space?
[11:07] - So we're looking at a space of about
[11:10] 30 to 40 meters in length
[11:12] and about 10 to 20 meters in width.
[11:15] The collection at the time was about
[11:18] 3 to 4 million I think.
[11:19] - That is intense.
[11:20] Yeah, that's wow.
[11:21] - It's a lot of fingerprints.
[11:24] - Now, today's system takes into account
[11:27] these little details along the ridges.
[11:29] It's called friction ridge analysis.
[11:31] And well, it's no surprise that
[11:32] combing through pigeon holes
for these would've taken weeks,
[11:35] but online databases today can
basically do it in minutes.
[11:37] (phone ringing)
[11:41] No way this phone works.
[11:44] Hello?
- Howdy, Gregor.
[11:46] Just trying to get a hold of you.
[11:47] - Why are you calling
me through this thing?
[11:49] (caller speaks faintly)
[11:50] You have no data?
[11:51] Just get Saily.
[11:53] - You know, I travel a lot for filming.
[11:54] I actually just got to London.
[11:58] I always wanna be able to
connect to the internet
[12:00] as soon as I land,
[12:01] and with the help of
today's sponsor, Saily,
[12:04] it couldn't be easier.
[12:06] First, you just scan the QR
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[12:09] then you search your
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[12:12] And next you just pick a data plan.
[12:14] And finally, during checkout,
[12:15] apply the coupon code Veritasium
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[13:00] So I wanna thank Saily for sponsoring
[13:02] this part of the video,
[13:03] and now back to our case.
[13:05] So if all the details
are painstakingly placed
[13:08] into these databases,
then where's the problem?
[13:12] How is Brandon Mayfield falsely accused?
[13:15] Well, say you have a mark from a scene
[13:17] and you wanna run it through
the US fingerprint database,
[13:20] you can't actually search the
database using the whole mark
[13:24] because you first need to identify
[13:25] a number of features on the print.
[13:28] These are called minutiae.
[13:30] It's where the ridge line split or end.
[13:33] - To even search the database,
[13:36] you need a minimum number
of minutiae points.
[13:40] It's very efficiently sorted,
[13:42] hundreds of million prints,
[13:43] but it cannot make an ID.
[13:45] So what it does, it pulls
out the most similar ones,
[13:49] at least 10, 20 up to
40 in some jurisdiction.
[13:54] And then the human
examiner has to compare.
[13:58] - [Gregor] This works in
theory, but the problem is
[14:00] how these minutiae are
identified in the first place.
[14:04] - What is interesting in my research
[14:06] published scientific reviewed research,
[14:09] the same thing one examiner
see only three minutiae
[14:14] and one sees 10 minutiae.
[14:16] So 10 minutiae is enough
to run the database.
[14:19] However, if the other are
only the three minutiae,
[14:23] they couldn't run it.
[14:24] So whether you find a criminal or not
[14:27] depends on the luck of the draw.
[14:29] Even if you give the same pair of prints
[14:31] to the same examiner
twice, 10% of the time,
[14:35] they will reach a different decision.
[14:38] - And these disagreements
are from controlled studies
[14:41] where the examiners had no
context about the crime,
[14:44] but in reality, they often do.
[14:46] As many as 42% of the requests
[14:48] that fingerprint experts process
[14:50] state whether a suspect
has a criminal record.
[14:53] - In a recent case that I was involved
[14:57] where a firearm was involved
[14:59] and a forensic firearm expert
[15:02] had to decide whether a
bullet was actually fired
[15:06] on the firearm, on the suspect.
[15:08] On the former submission form
[15:11] that was given to the forensic scientist,
[15:14] it said that it's homicide,
[15:17] it said the age of the
suspect and the victim,
[15:20] and it even said the race.
[15:22] It said the suspect is black,
[15:24] and the person who died
the victim was white.
[15:28] - For over a century,
[15:29] experts have held so much
trust in fingerprints
[15:32] that in the FBI case for Mayfield,
[15:34] the examiners claimed with 100% certainty
[15:37] that that was his mark.
[15:39] This likely happened because
when another fingerprint expert
[15:41] was brought in to verify the match,
[15:43] they probably already knew the verdict
[15:45] of the original analyst,
[15:47] and they probably also knew the stakes
[15:49] of what a match could mean for the case,
[15:51] which made it all the easier to agree
[15:53] with the initial verdict.
[15:55] Even the fingerprint expert
working for the defense
[15:57] agreed that the mark matched
Mayfield's fingerprint
[16:01] when in reality, it belonged to a man
[16:03] who had links to terrorist
organizations in Spain.
[16:07] This is the impact of conformity bias.
[16:09] - So all of this pressure,
[16:10] all of this context and intervention
[16:13] in the forensic science,
[16:15] I say to the police and the prosecutor,
[16:17] leave the forensic examiners alone.
[16:21] Give them independence of mind
[16:23] to make decision based on the
relevant scientific evidence
[16:28] and do the work rather than
telling them about the case.
[16:33] - Well, if there were issues
[16:35] with all these other techniques,
[16:37] why don't we just use,
[16:38] - DNA?
- DNA first?
[16:40] - Yeah.
[16:41] - DNA has got to be surely,
- DNA should be top.
[16:44] - It has to be DNA because,
- Okay, okay.
[16:46] - You already know everyone
have their own DNA.
[16:48] - But even DNA analysis can
fall prey to the same problems.
[16:52] Back in the 80s,
[16:53] you had to do this with a sample the size
[16:56] of a dime of blood or saliva.
[16:58] But today you can do it with
less than a pin hair's worth.
[17:00] In fact, just this year
a 61-year-old cold case
[17:03] was solved with just 0.4 nanograms of DNA.
[17:08] But the paradox is, the
increasing sensitivity
[17:11] of DNA analysis could
also be its downfall.
[17:15] In 2012, paramedics in
California responded to a call
[17:18] about a severely intoxicated homeless man.
[17:21] They treated him and
took him to the hospital,
[17:24] but along the way, they
also picked up traces
[17:26] of his DNA on their equipment and gloves.
[17:29] Then later that night,
they responded to a murder
[17:31] of a businessman and they
accidentally transferred
[17:34] the homeless man's DNA to
the victim's fingernails.
[17:38] Because of that, the
homeless man, Lucas Anderson,
[17:40] was charged with murder and
he faced the death penalty
[17:43] despite being hospitalized at
the time the crime occurred.
[17:46] He spent five months in jail
[17:48] before charges were finally dropped.
[17:51] - So this is trace DNA and touch DNA,
[17:54] where you can get this kind
of DNA transfer that happens.
[17:57] - I see how that could be abused easily.
[17:59] So my DNA could be in a
place I've never been before.
[18:01] - Yeah.
[18:02] - And if DNA is deposited
under the right conditions,
[18:05] say a dark dry place, it can
persist for hundreds of years.
[18:10] - And if, for example,
somebody touches a door handle,
[18:14] well, loads of people are gonna
be touching a door handle,
[18:16] so you're definitely going to get
[18:18] more than one profile off of there.
[18:21] - [Gregor] These samples
with multiple DNA profiles
[18:23] are called DNA mixtures,
[18:25] and they have been found to be
[18:26] the most common source of
error in DNA interpretation.
[18:29] - Some people shed more cells than others,
[18:32] so the majority of the
DNA that you're getting
[18:35] off of that door handle may not be
[18:36] from the last person who touched it.
[18:38] - The problem in interpreting a mixture
[18:40] comes down to how a sample gets analyzed.
[18:43] The most common way to do it
[18:44] uses short tandem repeats or STRs.
[18:48] DNA is made up of four nucleotides,
[18:50] G, A, T and C.
[18:52] And the SDR method looks
at how chunks of DNA,
[18:55] usually three to five nucleotides long
[18:57] repeat in your genome.
[18:59] For example, G-A-T-A, G-A-T-A and so on.
[19:02] For one person, they might
have G-A-T-A repeat six times,
[19:06] whereas another individual
might have nine repetitions.
[19:10] A standard SDR test will look at around
[19:13] 20 locations on your genome
[19:14] for where these repeats can occur,
[19:16] and it will count how many repeats
[19:18] you have in each location.
[19:20] - So if you are looking
at 20 of these markers
[19:23] and you've got one from
mom and one from dad,
[19:25] you're actually getting 40 different
[19:27] genetic markers coming back.
[19:29] So the chances of somebody
having the same combination
[19:34] of genetic markers as you
is around one in a billion.
[19:38] - Here's what a crime
scene sample containing
[19:39] just one contributor
looks like on an STR test.
[19:43] You can see how it's easy to compare this
[19:44] to a sample from a suspect.
[19:47] But if the crime scene sample contains DNA
[19:49] from multiple individuals,
[19:51] then their profiles will begin to overlap,
[19:53] all with varying signal strengths.
[19:55] And the more individuals in the mixture,
[19:57] the more difficult these
results are to interpret.
[20:00] With four or more individuals,
[20:01] it becomes increasingly hard to compare
[20:03] a clean DNA profile from
a suspect to the mixture.
[20:07] And now it's hard to
say whether the suspect
[20:09] was actually in the sample.
[20:10] You just can't tell which
peak belongs to who.
[20:13] It's kind of like having
five people talk to you
[20:15] at the same time.
[20:17] You can hear all the noise,
[20:18] but it's really hard to single one out.
[20:20] Now, some labs claim they
can reliably separate samples
[20:24] of up to five individuals.
[20:26] And to test this,
[20:27] the National Institute of
Standards and Technology
[20:30] ran a controlled study in 2013.
[20:33] They've sent out a DNA mixture
from a fictional crime scene
[20:35] to labs all across the US.
[20:37] Their aim to see how different facilities
[20:40] interpret the same mixture of
four people's DNA profiles.
[20:44] 69% of the labs got the analysis wrong.
[20:47] And despite the sample
being deliberately complex,
[20:50] only 21% of the labs
deemed the mix inconclusive
[20:54] and not possible to give a comparison on.
[20:56] After NIST published the study,
[20:58] new checks have been imposed
to address some of the issues,
[21:01] but there's still no lower limit
[21:03] on the quality or the
quantity of a DNA sample
[21:05] that labs are permitted to analyze.
[21:08] And labs themselves still decide
[21:10] if something is too mixed or too partial.
[21:13] Now, you might think that
[21:14] using the entire sequence
genome would be better,
[21:17] but that can actually introduce
different kinds of problems.
[21:20] Now, your analyst has
access to hair color,
[21:22] eye color, ethnicity,
[21:24] and that could introduce discrimination
[21:25] in the way the sample is being analyzed.
[21:28] - This is where the guidelines
[21:29] and the guardrails have to come in here.
[21:32] What are the genetic markers
that are being used for this?
[21:36] This is where the really interesting
[21:37] ethical questions come into it.
[21:39] People think that DNA is
like the silver bullet
[21:41] that will answer everything.
[21:44] And it is true.
[21:45] DNA evidence is incredibly powerful,
[21:48] it's amazing for identifying individuals,
[21:52] but DNA can never be taken out of context.
[21:57] - Now, the point of this
video isn't to bash forensics.
[22:00] I think it's still better
for us to live in a world
[22:01] where forensics exist rather
than one where they don't.
[22:05] But if we want to keep
calling forensics a science,
[22:08] we need to continue the work of the people
[22:10] who actually made this video possible,
[22:12] who've dedicated their lives
[22:13] to already reassessing the field
[22:15] and making it as accurate as it is today.
[22:17] Do you think it's fair calling
this a forensic science?
[22:19] - I still think there's science in it
[22:21] because you're trying to do the best
[22:22] with the information you have,
[22:24] which is often times what
science is trying to do is,
[22:27] with the information you have,
[22:28] this is the conclusions you make
[22:30] until you know something better.
[22:32] (gentle music)
[22:44] - Hey, one last thing.
[22:46] Last year we launched the
official Veritasium game,
[22:49] Elements of Truth.
[22:50] It's a trivia game with 800 questions
[22:52] covering science and technology,
[22:54] and we on the team get quite competitive.
[22:56] So every time we play
things get very saucy.
[22:59] See, there's this mechanic
[23:00] where you can't only guess an answer,
[23:02] you have to put down a
number between one and 10
[23:04] to gauge how confident you
are that your answer is right.
[23:07] So it gets very fun very quickly.
[23:09] The game is coming out later this year,
[23:11] so if you're interested in pre-ordering,
[23:12] you can click the link in the description,
[23:14] which will take you to the
Elements of Truth website.
[23:17] Thank you so much for your
support in this project.
[23:19] And as always, thanks for watching.