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December 26, 2024 42 mins

We've all heard it - local news reports identifying a body from dental records. But how does this work? Well, that's our job!

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Speaker 1 (00:01):
Welcome to Stuff you should know, a production of iHeartRadio.

Speaker 2 (00:11):
Hey, and welcome to the podcast. I'm Josh, and there's
Chuck and Jerry's not here, but she's here in spirit.
We're all flashing our pearly whites because we're in a
lineup and this is stuff I.

Speaker 1 (00:22):
Tried, or my case, front four of my pearly off whites,
because when they made me my new set of four
teeth to go upfront to replace my four teeth, they
were too white and they looked weird. Oh really, And
they said we can send them back and have them
staining them just a bit more, and I went, yeah,
we're gonna have to do that.

Speaker 2 (00:42):
Like Matt Dylan, and there's something about Mary.

Speaker 1 (00:46):
They weren't quite chick lit white, but they were enough
to where they looked a little different than the others.
And the others are just gonna, you know, as teeth
do continue to stay in a bit. So yeah, it's like, yeah,
why don't we go ahead and knock it down?

Speaker 2 (00:59):
And you should have just smoked a bunch of cigarettes, right,
done it yourself, saved some money.

Speaker 1 (01:05):
I don't think these implants will. That's the problem is
they don't stain, while the others are.

Speaker 2 (01:10):
Oh okay, well then yeah, you definitely need to hand
those off for staining in the lab.

Speaker 1 (01:15):
Yeah, I'm like, well, I was just smoked eighties cigarettes,
so today another and I thought we were done with forensics,
But who knew that lurking out there was the topic
of forensic dentistry, which we will learn very quickly as
in right now kind of can be divided up into
two things, which is identification of deceased people or peoples

(01:41):
from dental records, like when you hear like you know,
they perished in the fire, but they were able to
identify the body, and the much more controversial bite mark
analysis that had been widely used in court and is
now generally thought of by most dentists and people in

(02:01):
this line of work as junk science.

Speaker 2 (02:03):
Yeah, it's I mean, just from researching this, it's like,
what kind of judge is still allowing this in as evidence?
It's crazy.

Speaker 1 (02:10):
Yeah.

Speaker 2 (02:11):
Yeah, So I guess I just revealed my take on
forensic dentistry or bitemark analysis specifically, because the other version
you said identifying deceased people is really no, it's not.
It's pretty much set. Most I didn't read anybody who
was challenging it or it's legitimacy, And apparently it's been

(02:32):
really useful over the years because the teeth are the
strongest part of the body. They can survive fire, they
can survive exposure to chemicals that could just get rid
of the rest of the body. They can survive explosions
up to I think two thousand degrees fahrenheit. They can
take heat up to that as anyone who's made it

(02:53):
far enough in breaking bad nose that eventually, if it
gets hot enough, they'll pop like popcorn. But most of
the time, if a dead person who's unidentifiable comes into
a medical examiner's office, they have not been exposed to
that level of heat.

Speaker 1 (03:07):
Yeah, and even if the teeth themselves are struggling to
hang in there, tooth pulp or dental tissue on the
inside of that tooth is very resistant to environmental attacks
like incineration, immersion, like you can be underwater for well,
I was about to say a million years, but that's
probably not true, but immersion, trauma, decomposition, So extracting DNA

(03:32):
from the inside of a tooth is a pretty viable thing.
But before nineteen seventy four, all you really had going
was identifying victims of a disaster, usually a natural disaster
or human cause disaster. They did not really get into
crime scene stuff. Because in nineteen seventy five is when

(03:54):
that first became permissible in court, where a murder victim
had a bite on her nose and three forensic dentists
came along and said, hey, it's pretty clear this bite
came from this person. It should be maybe the exception
to the rule, but we should allow it in court
this time.

Speaker 2 (04:12):
Yes, And that was a very fateful decision because as
that case made its way through appeals and a final
appellate court upheld it, that also simultaneously not only convicted
the killer, it also it said, this is legitimate. Bitemark
analysis is admissible in court. It's set a precedent, and

(04:34):
that exception that those three forensic dentists in their defense,
you know, went to batfor for use in this particular case,
became the rule. And there was no longer like, hey,
this is not actually that great of an idea. It was, hey,
we've got this new way of prosecuting scumbags. Let's use
it to the max. And there was a really famous

(04:55):
case within just a couple of years of it becoming
widely used in American court sorts. That's still celebrated today.
Is one of the great successes of bitemark analysis because
it's not like every single case is worse than the last. Yeah,
but there's enough bad cases and enough people who've been
wrongly convicted and later exonerated based on bite mark evidence

(05:17):
that it should not It's not it should not be allowed.
You just go figure out who did it some other way.
Stop using bite mark analysis.

Speaker 1 (05:26):
Yeah, dozens of people, according to the Innocence Project. And
we should point out from nineteen seventy five until just recently,
like twenty sixteen is when they finally made affirm decision,
which you know, we'll hold onto that one, but that's
really when things changed. But I think the case that
you were talking about is I've forgotten Ted Bundy. In

(05:49):
nineteen seventy eight, a notorious serial killer Ted Bundy would
sort of wind up his serial killing career by wandering
into the Kyomegas already house at Florida State University and
bludgeoning and killing for students at sorority sisters there, including
one victim where he bit her and left very clear

(06:12):
bite marks. And those bite marks were instrumental in Ted
Bundy's conviction.

Speaker 2 (06:17):
Yeah, the two Kyomega women were who were who died
who did not manage to live with Lisa Levy and
Margaret Bowman. But he did some pretty terrible damage to
some the other the other two, I guess. But that
bitte mark apparently Ted Bundy had extremely crooked front teeth,
so much so and the bite mark was clear enough

(06:39):
that they used that bitemark analysis in part to convict
him for those murders. Those were he apparently admitted to
killing thirty women, possibly killed as many as one hundred
and so one of the one of the cases he
was prosecuted for were the Kyo Omega murders.

Speaker 1 (06:56):
Yeah, that's right. So that's a good setup. We should
just mention sort of as far as the identification, the
non controversial part. Adults usually have thirty two teeth, foreign sizers,
four canines, eight pre molars, twelve molars, and four wisdom
depending on if you still have those. And when you
go to the dentist, they you know, we've been to

(07:17):
the dentist, and they do a lot of notating. They
notate your teeth variations in your teeth changes in your teeth,
if you chip a tooth, any dental work you've gotten,
like crowns or fillings or bridges, or in my case
for implants, periodontal disease, receding gums. There are x rays
and there are just the tooth charts. And these are

(07:39):
the dental records that we speak of when they say,
you know, a body was identified, you know via dental records.
It's because of all this work that you get over
the years at the dentist. I guess if you, well,
this doesn't have so much to do with bitemark analysis,
I guess it could, but the records that seem like
are mainly about identification.

Speaker 2 (08:00):
Yeah, and also by laws, I think every state requires
dentists to keep dental charts on their patients, and then
they also have to retain them for set number of years,
depending on which state demands what. So they do come
in handy just the charts alone. Well, like, there's not
going to be x raysed with them necessarily, there's not

(08:21):
going to be any photographs just from the charts, and
the the coding systems that they've worked out to codify
teeth can conceivably give you enough information that you could
use it in some form of forensic dentistry. That's how
accurate the charts are meant to be.

Speaker 1 (08:40):
Yeah, for sure. So you know, we mentioned all the
ways teeth can hang in there and stay you know,
a part of your skull, and when other parts of
your body have deteriorated, teeth can shrink, they can become fragile,
but if you handle them gently and with care, you
can preserve them and lacquer. And what will happen if

(09:03):
you need to identify corpse usually is a dentist will
go to the morgue. They will surgically expose the jaw
and examine things. That's if you have, like you know,
a pretty recent dead body that hasn't decomposed too much.
If all you've got is a handful of teeth, that
still maybe enough due to those X rays and charts.

(09:24):
But if it's mass casualties, a dentist is gonna and
these are forensic dentists, by the way, it's a specialty.
They get a list of possible victims and then you know,
you start comparing different records of the different people to
try and sort out who is who.

Speaker 2 (09:40):
Yeah, Yeah, it takes a special kind of dentist to
do this kind of work, because by the time the cadaver,
the corpse has made it to the forensic dentist, everybody
else upstream has said, like, no, they don't have fingerprints,
their face is unrecognizable. It just keeps going on and
on and on until finally your last chance of identifying

(10:03):
the person is forensic dentistry. And they'll often, i mean,
like if it's a mass casualty, you know, you know
who is on the plane. Apparently that's when it comes
in handy a lot for plane crashes. You know, all
the passengers on the plane, You go get their dental records,
You hand them over to the forensic dentists and say,
good luck, can you match any of these teeth with
these charts? And they're they're i mean, they're a huge

(10:25):
part of a forensic team in like mass casualty events.
They're they're really important because again they're like the last
hope of some families getting closure, being able to like
give their loved one a funeral or something like that.
Like that's the role that they're they're playing. They're not
doing this because they like just playing with dead people's
teeth or anything like that. Like they are helping other

(10:48):
humans with their work by identifying disaster victims. I'm not
extending that to bitemark analysis.

Speaker 1 (10:55):
Yeah, yeah, for sure. There's a lot of things you
can sort of glean from looking at a person's teeth
about that person. It's not the most exact science, but
we know generally how fast teeth grow, about four micro
meats per day, So you can estimate someone's age based
on their teeth.

Speaker 2 (11:14):
Well, not only that, you can also like when your
teeth develop as a human, it follows a set pattern. Yeah,
so you can go and look at somebody's development, especially
if they're underage, I think twenty something or thirty five,
and say, well, they have they've developed this tooth, but
they haven't developed this tooth, so they're yeah, probably eighteenish.

Speaker 1 (11:35):
Yeah, exactly. They can get it in a wheelhouse. Sometimes
you can learn a little bit about someone's ethnicity because
you know, some ethnicities have teeth that are a little different.
Apparently some Native Americans and some Asian people have incisors
that have scooped out backs. You can determine sometimes some

(11:56):
socioeconomic background. If there's you know a lot of really
expensive restoration work, that'll tell you that they probably had
a lot of money or you know, at least money
to afford that. Also, the methods that are used are
used in some parts of the world and not in others,
like some geographic areas. Person's lifestyle, like if they were

(12:17):
a smoker, this is kind of fun. If you're a
pipe smoker, man, if you play the play the bagpipes, Yeah,
you have a very distinctive wear pattern on your teeth.

Speaker 2 (12:25):
Did you see any pictures of a skull with a
with a where from pipe smoking? Yeah, it's crazy. It's
like the person's teeth like curve up at some point,
like I'm basically I think it was the right side
of their face just from holding a pipe in their
teeth for years and years and years.

Speaker 1 (12:44):
Yeah, and then just sort of the obvious stuff like
a family member saying like, no, they were definitely missing
that tooth or that that you know, that distinctive crown
with the diamond CWB for Charles W. Chuck Bryant, I know,
I can't believe you got that. Still that was definitely
their mouth or that tooth was broken. So beyond just

(13:07):
dental records, like family members can sometimes help out.

Speaker 2 (13:10):
I also saw another lifestyle. One was something called a
tailor's notch. This is pretty arcane, but if you find
a tailor's notch, there's a chance that this was a dressmaker,
a tailor or something like that, because they hold pins
in their mouths.

Speaker 1 (13:24):
Oh yeah, as part of their.

Speaker 2 (13:25):
Profession, usually in their teeth, and when you do that
enough times, it actually wears a little indentation in the
tooth that you normally hold the the sewing needle in. So,
do you want to talk about the Black Death or
just keep moving on.

Speaker 1 (13:40):
Let's take a break. Okay, all right, we'll take a
break and we'll talk about the Black Death and then
dive into the more controversial bitemark analysis.

Speaker 2 (14:14):
So we promised talk about the Black Death. Apparently one
of the high profile I guess forensic dentistry cases recently
was a study that looked at the teeth of or
I think it extracted DNA from the pulp of the
teeth of medieval villagers who died from the plague. And

(14:35):
I guess they were able to exclude the plague in
some cases, like people had died and it was falsely
attributed to death from the plague. That seems almost inconsequential
to me because the other thing that they did was
definitively prove that you're seeing a pestis, which is a
bacteria I think, a bacteria that's carried by fleas typically,

(14:58):
So the rats came to town, the fleas around the
so the bacteria was on the fleas, and that's what
spread the black death, that's what they've long said. And
they extracted that from the DNA of the pulp of
teeth of medieval people who died from the plague definitely
died from the plague, and said, yep, here's your smoking gun.

Speaker 1 (15:16):
There's your problem, right, Yeah, And it was something this old.
A DNA isn't readily available. M DNA mitochondrial DNA can
also be very useful.

Speaker 2 (15:26):
And I also saw the oldest tooth that they successfully
sequenced a genome from by extracting DNA from the pulp
was six thousand years old, from about four thousand BCE.
Back in two thousand and five. They managed to do that,
and you know, those people are still talking about, like
I did I ever tell you about the four thousand
BCE tooth we extracted DNA from?

Speaker 1 (15:46):
Yeah, oh boy, the smell of that toothbulp O Oh good.

Speaker 2 (15:51):
God, that was awful. I was not expecting that.

Speaker 1 (15:55):
All right. So now this is where things get a
little hinky, because we're going to talk about the other
aspect of forensic dentistry, which is the very controversial, very
complex bite mark analysis, which and we'll get to the
admissibility of it now in a bit. But they still
do collect the evidence, which you know you should do.

(16:16):
I don't think anyone's saying, like, hey, stop even doing
this as far as evidence collection goes. But here's how
they do that. If you see a bite mark or
anything you think is a bitemark in a like a
murder case, Let's say you call in that forensic dentist
who's just sitting around like so happy. They don't have
their hands in a live human being's mouth at the time, right,

(16:38):
And they got to do it quick because time is
of the essence, because bite marks can change a lot
pretty quickly, and especially if a body has been deteriorating
for a few days, like the location of that bite
may be entirely different because the skin is slipping and shrinking.

Speaker 2 (16:54):
Yeah, that's a big one. Also, bruising and lividity can
also obscure a bite mark or change it or alter it,
so they often have to wait for the bruise to
heal if the humans still alive, or wait for the
lividity the pooling of blood to just kind of come
and go before they really examine it.

Speaker 1 (17:15):
Yeah, they're going to take pictures with a ruler next
to it. You've probably seen that in some movies I have.

Speaker 2 (17:20):
I saw in Silence of the Lambs.

Speaker 1 (17:23):
Right, oh, yeah, that's right. Bite photography is very specific
and very precise, or at least it should be, and
then you can magnify those photos and stuff. But while
they're doing this, the first thing that they're going to
identify is like was it a human bite or not?
And seems like a no brainer, like I could even
tell sure, But you found a study from twenty fifteen
that doesn't quite hold up. I mean, that's about animals

(17:46):
and human differences, right.

Speaker 2 (17:47):
Yeah, there was a twenty fifteen study that found they
used thirty nine experts. These were Board certified Forensic odontologists
or members of the American Board of Forensic Odeontologists, the
crediting body. I don't know why I went into that
much detail, but there you have it. The official people

(18:08):
in this study with this thirty nine experts. They showed
one hundred photographs of bite marks and said, okay, we
want some information about this. Are these Let's just start
with is this a human bitemark or an animal bitemark?

Speaker 1 (18:21):
The easiest thing in the world. Was this a dog
or an adult human biting this person?

Speaker 2 (18:26):
Exactly? And only eight percent of the photographs, so eight
of one hundred photographs. I just did that, meth and
I'm quite confident it's correct.

Speaker 1 (18:35):
Yeah, you nailed it.

Speaker 2 (18:36):
Could ninety percent of those experts. I don't know what
ninety percent of thirty nine is come to consensus that yes,
this is definitely human or yes this is definitely animal.
They did not believe. Yeah, they did not agree on
the other ninety two photographs.

Speaker 1 (18:53):
Yeah, I would think human and animal would be pretty
easy to tell the difference of you know, apparently not.

Speaker 2 (18:59):
Yeah, actually if the animals wearing human dentures at the time, right,
good point. Yeah, like that. You know that cartoon wolf
from the old timey nineteen thirties cartoon. I don't think
I know that, Oh, sure you do. He was always
like his eyes would pop out of his head and like.

Speaker 1 (19:17):
He was oh yeah, you know, like uh yeah, yeah,
I gotcha.

Speaker 2 (19:21):
So what else, Chuck?

Speaker 1 (19:23):
Well, this is a pretty disturbing but I guess helpful
thing that I never knew. After they inspect the body
for the bite marks and all that stuff, they will
actually cut out the bike mark and preserve it.

Speaker 2 (19:37):
They're like, can I take this home?

Speaker 1 (19:39):
Yeah, So they will cut the bipe mark from the skin,
preserve it and formaldehyde, and then make a silicone cast
of the bite mark, which makes total sense. I just
never thought about how gross that would seem.

Speaker 2 (19:51):
Yeah, it is pretty gross. I mean, the whole process
from starting to finish is fairly gross.

Speaker 1 (19:56):
In that case, what kind of bite marks though they
can they make?

Speaker 2 (19:59):
Well, I'm based on the kind of transfer pattern is
what they call it. And it's not just specific to
forensic idontology transfer patterns or what you're looking at when
you look at the rifling on a bullet to try
to identify what gun it came out of, which also
apparently is junk science fingerprints. You're transferring your fingerprints, so

(20:20):
it leaves a transfer pattern. Same thing with forensic idontology,
and the different kinds of forensic patterns are based on
the damage that the bites do. So if it scrapes,
like if you're I don't need to put it any
other way. That's considered an abrasian bite.

Speaker 1 (20:36):
Yeah.

Speaker 2 (20:36):
And artifact is when, yeah, when there's an actual part
of the body missing from because of the bite. It's
not just a bite mark, there's actually tissue or something missing,
like an ear lobe. I think is like Evander Holyfield's
ear lobe.

Speaker 1 (20:52):
Yeah, I was, I'd say mac Tyson bite.

Speaker 2 (20:54):
So he's got a fight on Friday.

Speaker 1 (20:57):
Oh is he fighting that guy Friday on Netflix? Shoot,
I'm not even gonna be here. I want to see that.

Speaker 2 (21:03):
I'll tape it for you on the VCR.

Speaker 1 (21:05):
You take it all right to me the tape. We
also have evulsions, that is when just some of the
skin is removed, and I guess not an entire piece
of the body. You have contusions, which is of course
a bruise. If it's profusely bleeding, it's a hemorrhage. If
it's a nice clean neat wound, then you have a
very precise spider and they call that an incision. And

(21:26):
then a puncture wound is a laceration.

Speaker 2 (21:28):
Yes, And then there's also the different like depths or
the obviousness of the bite mark is another category that
they use, and it starts from lowest to highest. It
took me a minute to figure this out because I
don't think the wording they used is really good. Agree,
a clear impression means that there was significant pressure used.

(21:50):
That's the lowest of the three categories. Yes, an obvious
one signifies medium pressure, which that to me just just
like shows that this is not accurate science. Medium is
a type of fry order, French fry order, not the
you know, depth of a bite mark, like medium is

(22:11):
so subjective, right, Yeah, all three of these are and
then noticeable. That seems to me like that would be
the least of the three. That's the most, the most
pronounced bite mark of all, because the biter used violent
pressure to bite down.

Speaker 1 (22:28):
Yeah, it should be obvious. Oh my god, and holy crap,
for the love of god, what was this person doing?

Speaker 2 (22:38):
Yeah, for sure. There's also some some other things that
the bier can do during the biting, if they you know,
if they like use their jaw a bunch. It's not
just like one bite where they clamp down. If they
bite in succession a few times, that was going to
leave a totally different mark from one that is going

(22:59):
to where they just clamp their jaw down or something.
If they move their tongue, it will move the skin
around and will affect the bite mark that's left behind.
We should have probably given like heads up at the
outside of this episode. Huh.

Speaker 1 (23:14):
Well, I think forensic dentistry is a creepy enough title, okay,
or maybe I'll title it forensic Dentistry colon enter at
your own Risk or something like that.

Speaker 2 (23:22):
Oh good one. And then there's another one too. If
the victim is being is still, it might which to
me means dead because nobody's gonna sit still. Well, they're
being bitten hard enough to leave a bite mark that
could be used against you in court. But you know,
if they're moving, that's going to affect the bite mark
that's left behind too. And then of course also the
kind of tooth profile they have too.

Speaker 1 (23:44):
Right, Yeah, for sure. I mean if you're if I
would have bitten somebody in a violent episode when I
had my front tooth or my two front teeth missing,
it would be pretty obvious when you saw that bite mark.
Ted Bundy, like you said, had crooked teeth, and so
that will leave a crooked impression obviously you need chips

(24:05):
on your teeth, are gonna make a more sort of
jagged impression.

Speaker 2 (24:09):
Yeah, Like if you ate a bunch of chips and
they're just stuck between your teeth, is that what you meant?

Speaker 1 (24:16):
Yeah, here's an ear lobe and some doriedo, So let's
put that in an evidence backing.

Speaker 2 (24:22):
You're welcome for the plug.

Speaker 1 (24:25):
And then braces. You know, if you braces or implants
or something or a bridge, that can leave a pretty
distinctive impression for sure. Once and this is sort of
how it used to work, but once they identify a subject,
they're going to get a warrant to take a mold
of a suspect's teeth so they can compare it. They'll
take a lot of pictures of their mouth and stuff opening, closing, biting,

(24:48):
stuff like that, and then in the old days, they
would go to court and compare those and a forensic
dentist would take the stand and say, hey, that that
bitemart looks like that person's mouth me jury. That can
be a major reason why you convict.

Speaker 2 (25:05):
And in some cases they would say things like with
one hundred percent certainty.

Speaker 1 (25:10):
Yeah.

Speaker 2 (25:11):
Another thing that they say too, that we'll find that
seems to not be at all true, is that each
person's arrangement and teeth, like your mouth, everything inside your
mouth is totally unique, like your fingerprints. And that apparently
is not true at all, But you'll find it all
over the internet as fact.

Speaker 1 (25:31):
Yeah, I mean, there are some professional dentists, in forensic
dentists that still believe that. I mean that thing I
sent you was from last year, yeah, and is on
the National Institutes of Health US government website, and those
four accredited dentists dental experts flat out say like a
person's bite mark is unique like DNA or fingerprints. When

(25:56):
and I guess we should probably take a break and
get into the studies and stuff like that. But it
seems like study after study is kind of confirmed that
is just not the case.

Speaker 2 (26:04):
Well, let's take that break and we'll come back and
we'll talk about all the controversies surrounding bitemark analysis as
a part of forensic odontology.

Speaker 3 (26:12):
Man, that's a mouthful, all right.

Speaker 1 (26:40):
So you did some extra digging, and you know it's
pretty clear from doing the research that this is basically
known as junk science now to most people. Despite those
four people who wrote the article on the National Institutes
of Health. But there was a review in twenty twenty
two in a report from the NIST. What does that

(27:02):
stand for?

Speaker 2 (27:03):
The National Institute of Standards and Technology. They're like a
federal agency, if I'm not mistaken.

Speaker 1 (27:09):
Yeah, okay, So they released this report that said and
there were previous reports that we'll talk about too, I guess,
but this is the most recent that said BYTEmark, analysis
is not real science, and it's based on these three
sort of faulty premises, one which you already mentioned, which
is that a person's dental pattern is unique to that person.

(27:32):
And you know, there haven't been any studies that really
confirmed this. There was a twenty thirteen study from the
United Arab Emirates that found I think there's is that
sort of a dental capital of the world because I
saw a lot of dentists from like Saudi Arabia and AE. Yeah.

Speaker 2 (27:50):
No, I didn't know that. I didn't see that.

Speaker 1 (27:52):
Maybe I have a hunch that that's the case, so
maybe someone will confirm or deny that. But that study
found that fifty one percent of the two thousand dental
charts that they examined were unique, some one more than
half and the rest were identical to at least one other.
The only thing I'll say in defense is that it

(28:12):
may not be truly unique, but if forty nine percent
are unique, then that's unique enough to talk about. Maybe
not to be used in court, but enough to talk about.

Speaker 2 (28:26):
Yeah.

Speaker 1 (28:26):
Yeah, in my opinion, yeah for sure.

Speaker 2 (28:28):
But the fact is that study, and we should also
caveat that with the fact that this study used dental
charts only, and they made sure that they were highly
high quality dental charts that they examined. But the fact
that they were able to find dental charts that were
identical between two people totally undermines the the idea that

(28:53):
everybody's mouth is unique, everybody's teeth arrangement is unique.

Speaker 1 (28:57):
It seems like about half of them are. Yeah, if
you go by the data here.

Speaker 2 (29:00):
Yeah, and this was two thousand dental charts. They didn't
choose like three. Like this was a pretty decent, high
quality study, And yeah, I think it totally undermines that.
But like you said, yes, there's also enough uniqueness that
you can kind of use this. And I think, like
you said, nobody's really saying, like stop doing bitemark analysis entirely, right,

(29:24):
and the actually in their defense, the American Board of
Forensic Odentology says, they basically admit, like, hey, we made
some mistakes in the past, we've cleaned up our act,
we've revised our guidelines, and now if you're a legitimate
forensic odontologist, the furthest you will go is to make
three different calls. One exclude, meaning that this person's teeth

(29:50):
could not have possibly made the bite mark that you're
showing me, cops.

Speaker 1 (29:55):
Yeah, not exclude.

Speaker 2 (29:57):
Which is only saying it's pos I'm not going to
go any further than that, but it's their their teeth
resemble enough this bite mark pattern, this bite pattern, that
it's possible that this person made it, and then inconclusive,
and that's as far as they're supposed to go. They're
not supposed to in that sense, they're not I guess
you could testify those three things. But if the prosecutor's like, okay, so,

(30:21):
so not exclude, you're saying it's his right, They're they're
supposed to bail essentially at that point. They're not supposed
to go any further than that. That's the standard in
the guidelines for forensic dentists doing biite analysis bite mark
analysis today, but there's still plenty of people out there
who are going beyond that.

Speaker 1 (30:38):
Yeah, and you know that's the kind of situation too
where you also have to really educate a jury over
like the data on what that really means, you know
what I'm saying, and say like, hey, half the time,
these aren't unique, So you have to understand that going in.
So you know that that was the first thing, and

(30:58):
you know that there was that one case that you
sent where and this kind of factors into number two.
And number one was that they're they're unique. Number two
is that the patterns can be accurately transferred to the
human skin, because we've already talked about the fact that
there can be a lot of distortion by skin's elasticity,
and if the person like sort of does a sawing motion,

(31:21):
it completely distorted the bite mark. But you sent that
one case of the guy who was convicted who was
missing a tooth entirely, which should show a pretty clear like, hey,
we can exclude this one because the bitite mark didn't
have a gap. But they were like, yeah, but if
he grinded his teeth and kind of did a sawing motion,
it could look like this, and he was found guilty,

(31:43):
you know, and he was not guilty.

Speaker 2 (31:44):
Yeah, he was sentenced to jail, I think, was that
Roy Brown?

Speaker 1 (31:48):
Yeah, in two thousand and seven.

Speaker 2 (31:50):
Okay, so yeah, he spent almost twenty years in jail,
fifteen years from ninety two to two thousand and seven,
largely based on that bite mark analysis testimony.

Speaker 1 (32:01):
Yeah, and the both forensic dentists that worked on that
case recanted their testimony, right, like completely.

Speaker 2 (32:08):
Yeah, that was a big one too. I think maybe
in one of those cases where they were appealing it.
I don't know if it was Roy Brown's, but there
have been plenty of forensic on ontologists who have gone
back and been like, what I was saying apparently is
not right or grounded in science. I recant my testimony,
and at least one judge that I read was like, well,
we didn't really need you. The jury could have come

(32:29):
to the same conclusion that the bitemark matched their teeth.
So I'm not going to overturn this case, which is
nuts in and of itself. But Roy Brown is far
from the only person who has been exonerated after being
convicted on bitemark analysis too, right, Like, haven't there been
like at least twenty six people.

Speaker 1 (32:50):
Yeah, at least twenty six That DNA evidence is now cleared,
where bite mark analysis was, if not the smoking gun,
like a pretty key part of the jury's you know finding.

Speaker 2 (33:00):
Yeah, remember when I was saying, some expert witnesses on
the stand say like this, it's one hundred percent match.

Speaker 1 (33:07):
That happened.

Speaker 2 (33:07):
A good guy named Roy Cron he did ten years
based on BikeE mark analysis. Because you got to understand,
if you're a juror and the prosecution is saying, like
this person is an expert in forensic odentology, and that
expert tells you, the jurors, there is one hundred percent
match between that man's teeth and this bite mark on
this murder victim, it's going to be tough to overlook

(33:29):
that For the average jur I would.

Speaker 1 (33:31):
Guess, yeah, for sure. And you know, the big change
that you were talking about with just excluding that came
about in twenty sixteen. We've mentioned some other studies. There
was one we didn't mention in two thousand and nine
when the National Academy of Sciences released a report about
a lot of problems with a lot of forensic science,
but one of those was bitemark analysis, and they basically said,

(33:55):
and this was in two thousand and nine and it
still took till twenty sixteen to make that change official,
was they said, there's no scientific studies that support the
assertion that bite marks provide sufficient detail for positive identification.
And then a few years after that, doctors from the
American Border Forensic Identology, like, we said, that's the sort

(34:16):
of the main body or is the main body? Participants
in a study there of certified dentists, an overwhelming number
of them couldn't even agree whether they were looking at
a bite mark at all.

Speaker 2 (34:26):
Yeah. There was another thing too, I think from that
same study where they took the same experts and went
back to them eight weeks with the exact same photos
they'd shown them eight weeks before, and some of those
experts didn't even agree with their previous assessments.

Speaker 1 (34:40):
Wow.

Speaker 2 (34:41):
Yeah, so that was and they weren't like, hey, you
said this before, what do you think now? It was
like they I think they thought that this is a
new set of bite marks and they were just basically
guessing is what they found. So it's been pretty thoroughly debunked,
but people still use it. The Innocence Project really taken
an interest in this, and I think rightfully. So we

(35:04):
did an episode on that with guess Paul Is on
Remember Correctly and Yeah. So they're a group that go
around and basically free people who were railroaded or wrongfully convicted,
usually based on DNA evidence that wasn't heard in their case.
And so one of the things that they've done is
taken interest in bite mark analysis. And one of the

(35:25):
roles they play now is I don't know how they
keep their finger on the pulse, but if a prosecutor,
which is very rare these days from what I understand,
tries to introduce bite mark analysis into a case, the
Innocence Project will show up and be like, we object
to that. This is not science, this should not be admitted.
And I think they're fairly successful.

Speaker 1 (35:45):
They throw tomatoes at them, for sure. There was another
case you found pretty striking when a guy named John Kunko.
He was convicted of rape and assault in nineteen ninety one,
and the main evidence that got him convicted was identification
of his voice by the victim, a comment he supposedly

(36:06):
made at a party, and then bite mark on the
victim's shoulder. All the evidence was a problem. The comment
that the party that he supposedly made was not corroborated
by I always have trouble with that word.

Speaker 2 (36:19):
It's a hard one.

Speaker 1 (36:21):
Corroborated by any other people at the party. The voice
ID was made from a police officer's imitation of Kunko
and his lisp to the victim, so I have no
idea how that got through. And then I believe the
bite mark was infrared light analysis of a bite mark

(36:42):
that had already healed.

Speaker 2 (36:43):
This is a big one. So there was a forensic
onontologist from Mississippi named Michael West, and he essentially just
changed careers to be an expert witness in forensic onontology.
That's how he made his living. And he came up
with a technique called the West phenomenon, wherein you can,
according to him, using some special goggles and a UV light,

(37:04):
you can basically resurrect a bite mark that's healed years
later and see it well enough that you can compare
it to a suspect's bite and use it to convict.
He totally made it up, apparently, at least in the
first case that he used it on. He took photographs,
but he wouldn't share him with anybody, So it was

(37:25):
just his testimony that this person was convicted on, and
it became a tool of the trade. So other people,
including John Conco, were convicted in part because of this
West phenomenon, which was part of an overall junk forensic science.
So this is the junkiest of the junk that people
were being convicted on.

Speaker 1 (37:44):
Did he also sell the special goggles on his website?

Speaker 2 (37:47):
Yeah, but he sold them as X ray goggles that
you could look right through people's clothes with.

Speaker 1 (37:53):
Yeah. It was a picture of him with his uh
looking at his hand and the bones.

Speaker 2 (37:57):
Yeah, with exclamation points come up off of his head.

Speaker 1 (38:01):
Yeah. So yeah, I mean this is everything changed in
twenty sixteen. One of the big things that happened, and
I think there was a case in Texas a guy
named Stephen Cheney was released by the Texas Court of Appeals.
And this is the Texas Court of Appeals. They're not
big on releasing, right, you know, convicted criminals. I noted
that too, But the Texas Forensic Science Commission in twenty

(38:24):
sixteen because of this you know, kind of fraudulent bitemark
evidence in Stephen Cheney's case, they were like, we need
to stop this, and I think that was kind of
a big case that kind of, you know, really jump
started the whole We maybe not scraped the whole thing,
but where they ended up, which is it can exclude,
but it can't positively identify.

Speaker 2 (38:42):
Yeah, you just use it to exclude. That's what most
people can agree on for bitemark analysis is as far
as they Yeah, Chuck, to ever tell you about Paul
Revere in forensic id antology, No.

Speaker 1 (38:56):
But hey, it's a good little historical cherry on top, right.

Speaker 2 (38:59):
Yeah. So Paul Revere in addition to being a blacksmith,
he was a dentist too, and one of the things
he did he was one of the first forensic ononologists
who used dental records based on his own knowledge too.
He made, you know, dental work for a lot of
people in the Revolutionary War, and he identified some of
those people, including doctor Joseph Warren, the man who sent

(39:22):
him on his fateful ride where he shouted the British
are coming, the British are coming.

Speaker 1 (39:27):
Boom pal.

Speaker 2 (39:28):
Yeah, pretty amazing. Huh.

Speaker 1 (39:30):
Yeah, that's a good one. Thanks.

Speaker 2 (39:32):
I think that's it for forensic onontology, right.

Speaker 1 (39:36):
Yeah, and man, that may be it for our long,
long running forensic suite. I can't believe that there could
be anything else, But I also said that last time.

Speaker 2 (39:44):
Yeah, I disagree, but yes, we'll find out. I think
I'm going to go find something.

Speaker 1 (39:50):
Maybe, I mean someone will write in and be like, guys,
you've covered crimes and clean up. That's better analysis, fingerprinting.
I mean, the list goes on and off.

Speaker 2 (39:57):
Yeah, you forgot forensic foot smelling, Go do that one.

Speaker 1 (40:00):
Maybe what I didn't know about that's it. It was
the dog I smell Frido's right.

Speaker 2 (40:05):
Nice. Oh, actually I can do this old school too,
because if you want to know more about forensic demistry,
you can go check out a how stuff works article
that we use in part for this episode. That is
kicking at old school, isn't it.

Speaker 1 (40:17):
Yeah, one of the rare articles that we didn't cover
that is still good for us.

Speaker 2 (40:21):
Yeah. And since I kicked at old school, then it's
time for listener mail.

Speaker 1 (40:28):
All right, I'm going to call this another ADHD follow up.
This is a this is a good one. Hey, guys,
I had to write in after the ADHD episode. During
the first episode, I had to pull over into a
parking lot because, honestly, guys, I started crying. Oh wow, Yeah,
I have ADHD and I have never had my life
explained on a podcast before. Everyone's experiences are different, for sure,

(40:51):
and I think you did an incredible job explaining the
base challenges. I also appreciated Chuck's hesitancy to call it
a disorder. It is to find it disorder, but so
there's nothing wrong medically with calling it one. But it
does hurt just a little, even as an adult, when
people call it a disorder without thinking about the person
who has it. I appreciated the optimism with which you

(41:13):
both spoke about the challenges and how they can be managed,
especially Josh. The only thing I would add to that
is the subtopic would be to find people who accept
you before they try and change you. When I feel
that people love and accept me as me, I am
far more willing to accept their help with managing my ADHD.
Don't approach someone like you're going to fix them. Approach

(41:34):
them because you love them, and they will receive your
honest offer to assist.

Speaker 2 (41:39):
Man. That is some good ADHD advice right there.

Speaker 1 (41:43):
And just good life advice. Your podcast reminded me that
there are a lot of people out there like me,
and I hope that a lot of people out there
are trying to take this particular challenge do amazingly positive
things with it. And that is from Steve.

Speaker 2 (41:56):
Thanks a lot, Steve, what a great email.

Speaker 1 (41:58):
Yeah, appreciate it, Steve. That those episodes were a big
deal for us for a lot of reasons, and it
seems like people responded, so we're proud of.

Speaker 2 (42:07):
Them for sure. If you want to be like Steve
and tell us that you had to pull over because
you were so overcome by something we did or said,
we love that kind of thing, especially if it was positive,
not because it was so terrible that you had to
pull over. But even if that was the case, you
can still email us either way. Send it off to
Stuff Podcasts at iHeartRadio dot com.

Speaker 3 (42:29):
You Know, Stuff you Should Know is a production of iHeartRadio.
For more podcasts my heart Radio, visit the iHeartRadio app,
Apple Podcasts, or wherever you listen to your favorite shows.

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