A Question of Identity Catching History's Criminals: The Forensics Story

In the act of murder,

there is a weapon...

a crime scene...

and a body -

all vital evidence

in the hunt for the killer.

It's a game of cat and mouse

between police and murderer

that used to favour the criminal,

but then something happened

that swung the odds in favour of justice...

..the arrival of forensic science.

I'm Gabriel Weston.

As a surgeon and writer, I'm fascinated by the work

of the forensic scientist and the murders they've helped to solve.

In this series,

I'll explore the cases that transformed criminal investigation,

through poison and acid...

fingerprints and blood.

From the earliest days

to the cutting edge of modern forensics.

There will always be those who believe

they can commit the perfect murder,

who think they can conceal their victim's identity

as well as their own,

but forensic science has emerged as a formidable force

to challenge the killers and bring them to justice.

The history of crime is full of anonymous corpses -

bodies mutilated to the point where identification

was simply impossible.

They are the murders where the body itself presented

the main challenge to investigators and, as a surgeon,

they're the cases that I'm naturally most interested in because

they're the ones that could only be solved using medical expertise.

I'm going to trace the rise of forensic science

through four breakthrough cases,

from charred bones to DNA -

all questions of identity.

The first began here, at Harvard Medical College, Boston,

on November the 25th, 1849.

Inside one of the laboratories, George Parkman lay dead...

murdered...

by Professor John White Webster.

In a heated argument over unpaid debts,

Webster struck Parkman over the head...

..killing him outright.

Webster suddenly had more than money to worry about.

He was now a killer.

Webster had little time to cover his tracks.

His victim was no ordinary member of the public.

George Parkman was a man of considerable standing

within Boston society.

As a respected Harvard academic, moneylender and landowner,

he was well-known across the city,

so his disappearance was quickly reported to the police.

The authorities embarked on a huge citywide hunt for the missing man.

Even the river and Boston Harbour were dredged,

but there were no signs of George Parkman to be found.

Somehow, Professor Webster had managed to make

the body of his victim simply vanish.

The city was buzzing with many wild theories of what

might have befallen George Parkman,

but one man alone suspected the truth.

Ephraim Littlefield, a janitor at the Harvard Medical College,

had witnessed Parkman entering the building,

but never saw him leave,

and now Professor Webster was acting out of character.

His laboratory door, usually open, was locked.

FIRE ROARS

From beneath the door,

Ephraim Littlefield saw Webster making repeated visits to the

laboratory furnace and a terrible question grew in his mind.

If Webster wanted to conceal a body, where would he hide it?

As a janitor, Littlefield knew every inch of the college...

..and taking matters into his own hands,

he broke into a sealed vault

connected to Webster's laboratory toilet...

..and there he discovered human remains.

Thanks to Ephraim Littlefield, the police had a body on their hands.

The vault underneath Webster's toilet

was full of hacked-up limbs and, locked inside a chest in his lab,

they found a whole torso with a left thigh stuffed inside it.

All the circumstances pointed to it being George Parkman...

..and now Professor John White Webster was

arrested on suspicion of his murder.

Police recovered almost a complete body from

in and around Webster's laboratory.

The head, however, was missing and this was crucial.

Without it, they would struggle to identify the body.

But once again, the janitor Littlefield led the way.

He showed them to the laboratory furnace.

Inside were the cremated ashes of a human head.

This was Webster's attempt to obliterate the identity

of George Parkman...

..but destroying a skull is a far harder task than Webster realised.

To demonstrate, I'm going to recreate the grisly affair.

This is a sheep skull.

It's not a human skull,

but in terms of hardness and density,

it's remarkably similar,

and I've come to this amazing incineration unit

to see what happens when we put this skull in the furnace.

MACHINE WHIRS

This incinerator is used to cremate animal carcasses

and can reach temperatures in excess of 1,000 degrees Celsius,

and the skull is going to spend several hours inside.

I'm curious to see how much will remain.

I expected I'd have a pile of ashes here

but in fact, it looks very much as it did before.

Now, in these circumstances, what usually happens is that

the bony remains are put through something called a cremulator,

which grinds them up into what we would think ashes look like,

and what I'm going to do now is try and mimic that process

with this hammer, and see if I can destroy what's left of this skull.

Now, that's what Parkman's killer would have had to do...

..but Webster failed to complete the job.

Inside his laboratory furnace was a partial jawbone and some teeth...

..and it was these tiny fragments of a human being

that would completely change the course of forensic science.

The 19th century saw the emergence of dentistry

as a respected branch of medicine.

Bad teeth could now easily be replaced by dentures.

In making these, dentists kept accurate models

of their patients' jaws and teeth -

in other words, dental records.

And in a stroke of luck for detectives,

George Parkman had bad teeth.

His dentist, Dr Nathan Keep, had crafted him

an ornate set of dentures.

Rachel Bairstow is curator

at the Museum of the British Dental Association.

Parkman's dentures would have been made by taking a beeswax impression

of the mouth and then a plaster cast would have been

taken of that, and it was likely that he had

a metal denture of some sort, with some porcelain teeth attached.

You can see the clasps here,

This is how it anchored into place around existing teeth,

so it made a very good fit.

The craftsmanship was amazing, you know,

hammered into place by hand,

-to get the best that you could at that time.

-Yeah.

It would have been a very unique set.

Webster's trial began on the 19th of March, 1850.

When dentist Dr Nathan Keep took the stand,

he had with him his models of Parkman's jaw and denture...

..and also the fragments of bone found in the laboratory furnace.

So what did Keep do in the court of law?

So, he would have brought in the plaster cast model that he had

and this is the point where it would have been married up with

the items that were found, so the jawbone and the teeth.

The teeth would have been inserted into the jawbone

and then the denture plate would have been inserted over the top.

The jury can have had no doubt that this was Parkman in the furnace.

This was the legal birth of forensic dentistry.

On the basis of the dentist's testimony,

the remains were confirmed as belonging to George Parkman.

The janitor Littlefield collected a 3,000 reward

for his efforts...

..and John White Webster was sentenced to death.

SIREN WAILS

Today, forensic dentists are called upon

in the most tragic of circumstances -

in situations where only dental records can confirm

the identity of the dead -

but dentistry can do more than just identify

the victims of crime or disaster.

Here at the University of Cardiff Dental Hospital,

forensic scientists are turning their attention toward the criminal.

It's not unusual for a killer to leave bite marks on their victim

and these can be used as evidence in murder cases.

The idea is that if you can marry the bite marks to the teeth

that made them, you can catch the killer,

but recently in the USA, certain convictions that were secured

using this kind of evidence have been overturned

and the whole reliability of bite mark analysis

called into question.

To demonstrate why,

I'm leaving some bite marks of my own on this clay arm

and taking it to forensic dentist Romina Carabott for analysis.

So, first of all, we've got different pressure that has been applied,

so some of them have gone quite deep, whereas others,

like what we've got here, have stayed on the surface of the clay.

We've also got a curved surface here and that will affect

the shape of the print that the tooth would leave.

To analyse bite marks,

forensic dentists take high-resolution photographs,

but a 2-D image doesn't represent

a three-dimensional surface accurately,

so getting precise measurements from a curved body part -

like an arm - is difficult.

It's further complicated by the skin itself,

which swells and bruises around the mark.

Combined, these factors can make it extremely difficult

to make an accurate bite mark analysis...

..and that's what makes this type of evidence easy to

question in a court of law,

but imaging specialist Sam Evans is working with Romina to

develop a new 3-D technique that could provide

a more accurate way of measuring bite marks.

This is a modified SLR camera, with a stereoscopic lens

on the front that takes a pair of images,

so then software that's designed specifically for this camera

can create 3-D images.

CAMERA SHUTTER CLICKS

Sam feeds his photos into specialist imaging software

that produces a 3-D model.

This means the bite mark can be analysed much more accurately

than with a simple photo.

What are we looking at here, Romina?

The software has constructed the curvature of the arm

with the bite mark on it and so now we can rotate it around

and we can analyse each different part of the arm.

When you're actually using this technology,

how do you measure the tooth to see if the tooth fits the bite?

Say, for example, I want to take a measurement of the width

of the arch, the distance between the mark of the left canine and the

right canine, then we're going to just draw a line there and, because

the camera is calibrated together with the software, it facilitates

and increases the chances that I am going to be as accurate -

as precise, rather - as possible in my conclusions and analysis.

This work shows how forensic science is constantly seeking

new ways to establish identity.

It's long been a defining characteristic of the field.

After the murder of George Parkman in 1850,

new forensic techniques emerged,

and with them, a new breed of scientist -

the forensic pathologist.

They used their knowledge of human anatomy to help solve crime.

Killers now had to go to extreme lengths to obscure

the identity of their victims.

This area, just a few miles north of the Scottish border town of Moffat,

is known as the Devil's Beef Tub.

It's a place of outstanding natural beauty,

but it also has a dark and grisly past.

On September 29th, 1935,

two women were walking exactly where I have been now

and, as they crossed the bridge, one of them happened to look down

and she saw something very strange in the ravine below.

The stream was littered with discarded parcels.

Looking closer, she saw something horrific...

a human arm.

When police arrived, an even grimmer picture emerged.

More bundles were discovered -

each contained decomposing human remains.

18 body parts, as well as assorted fragments of bone and tissue,

were found up and down this stream.

Some had been wrapped in paper,

some were just lying in the water.

The remains were mutilated beyond recognition -

it wasn't even possible to tell

how many victims there were at the scene.

Forensic pathologists from Glasgow

and Edinburgh Universities were called in.

They were led by Professor John Glaister Jr.

To their expert eyes, the jigsaw of body parts started to tell a story.

It was clear that the murderer had gone to great lengths to

remove all traces of identity from their victims.

Fingertips had been carefully dissected out at the joint.

Teeth had been pulled from the upper jaw without doing any damage to

the surrounding bone,

which suggested the expert use of dental pliers.

They knew they were dealing with a murderer who probably had

medical training.

But who were the victims and who had killed them?

The remains were sent to Edinburgh University, where a team

headed up by Glaister, and college Professor James Brash,

set about reconstructing the victims.

It was a monumental challenge.

Painstakingly sifting through the remains,

they established there were two victims...

..both female.

One six inches taller than the other.

Analysing the skulls, they revealed a further critical detail.

These lines look like cracks,

but they're actually joints called sutures

and they enable the skull

and the brain to grow as we age, and they don't fuse until about 40.

Now over here, we've got an X-ray of the skulls found at the scene.

The one here has got the suture lines almost fused,

which means that this would have belonged to somebody

in their mid-to-late 30s, and this compares quite noticeably with

the one on the other side, where the suture line is quite noticeably

open still, and would have belonged to somebody in their early 20s.

The suture marks in the skulls told Glaister and Brash

how old the victims were.

While they continued to analyse the remains,

the police carried out more conventional detective work...

..and they had a lead.

One of the bundles was wrapped in pages from the Sunday Graphic.

It was a special edition,

only available in the Morecambe and Lancaster district,

and a young woman had recently been reported missing in that area.

The missing person was 20-year-old Mary Rogerson.

She worked as a live-in nursemaid for Isabella Ruxton, in Lancaster.

The thing was that 34-year-old Isabella had also disappeared.

Both missing women lived at number two Dalton Square

with Isabella's common-law husband,

a Dr Buck Ruxton.

Ruxton was a respected GP in Lancaster,

but beneath this veneer lurked a paranoid personality.

He'd been reported to police on two previous occasions

for threatening to kill his wife...

..and neither his wife Isabella nor the maid Mary had been seen

since the 14th of September.

A search of the house at two Dalton Square raised serious concerns.

Clothing and carpets had been burned in the back yard.

Blood stains were found in the bathroom.

It was enough for police to question Buck Ruxton on suspicion of murder.

The similarities between the missing women

and the corpses in the mortuary were striking.

Both women were precisely the right age

and Isabella was even six inches taller than Mary.

But in the cold light of day, these were just similarities,

hardly the kind of hard evidence necessary to establish

identity or even guilt.

Ruxton himself claimed he'd never even been to Moffat,

but then Glaister had an idea.

He obtained recent photos of Isabella and Mary,

then he took the skulls recovered from the stream

and photographed them using the same camera

and from precisely the same angle.

What he did next was a stroke of genius.

He took the original photo

and superimposed it over his own macabre recreation.

And the result is astonishing.

It's almost like an X-ray.

You can see the dead skull peering out from behind the living picture.

The angle of the jaw is perfectly in line,

the orbit of the eye is in the right position.

The bridge of the nose is perfect.

Glaister and Brash were absolutely sure that the missing women

were the corpses in the mortuary.

Eventually another body part was found -

a forearm with the fingertips intact.

The prints matched those taken from Mary Rogerson's room

at two Dalton Square.

The identity of the victims now seemed beyond doubt,

but there was one more key piece of evidence

that would point to the killer.

In any murder case, establishing the time of death is vital.

It can help link the murderer to the victim and, in the 1930s,

an area of science was about to enter the forensic realm

that would make estimating time of death much more accurate.

When the body parts were discovered,

they were decomposing and riddled with maggots.

But Glaister didn't just dispose of these, he preserved them.

These are the actual maggots

recovered from the remains of Isabella.

Glaister took them to Dr Alexander Mearns at Glasgow University.

He was an expert in entomology, the study of insects.

From the state of the bodies, it had been estimated that the victims

died around the 19th of September,

but the maggots told a different story.

Using his expertise,

Mearns was able to deduce that the maggots had been hatched from eggs

laid by a bluebottle 12 days before the remains were discovered,

so death must have occurred around the 15th of September.

It was close to the last time that Isabella was seen alive

in Lancaster, just before entering the house

she shared with Buck Ruxton.

Police were convinced that Ruxton killed his wife

late on the 14th of September.

The act was witnessed by the unfortunate maid Mary,

so she too had to die.

He dismembered both bodies in the bathroom,

a fact confirmed when human flesh was found within the plumbing.

He then drove to Moffat and dumped the remains,

where they would be discovered two weeks later.

Ruxton's trial took place on 2nd March 1936

and science took centre stage.

Each and every discovery was laid out for the jury in the most

extensive display of forensic evidence ever seen

in the British courts

and it destroyed any hope Ruxton may have had of being found not guilty.

At the end of the 11-day trial, the jury were in no doubt.

The two bodies found in this stream were Mary and Isabella

and Ruxton had killed them.

He was sentenced to death.

It was the first time entomology had been used as part of a murder

investigation in the UK.

Today, it's often the only way to estimate the time of death.

Knowing when an insect began to lay eggs on a corpse

allows investigators to establish

the minimum length of time since a murder occurred.

Dr Martin Hall is a forensic entomologist

at the Natural History Museum.

He's assisted the police in over 150 cases, most of them murders.

He's conducting new research

to increase the accuracy of the technique.

Oh! So...

-Not a very pretty sight.

-Oh, what a sight. No!

-No, it's not.

-But, um...

Martin, just very broadly speaking,

why do you have a pig's head in a suitcase out here?

It might seem a bit bizarre,

but what we're trying to do is to work out

what effect a body being disposed in a suitcase has

on the insect fauna attracted to it.

A postmortem is due to take place this afternoon

after a women's body was found in a suitcase.

A number of recent murder enquiries have begun

with the discovery of a body inside a suitcase.

Martin hopes his research can reveal how this method of disposal

affects his calculations of the time of death,

as a fly can't lay eggs directly on a body

if it's locked behind such a barrier.

He has observed how, instead,

eggs are laid around zips and small holes.

The maggots squeeze their way in through these tiny spaces.

Martin's testing how quickly this happens

in different temperature conditions.

Why aren't there very many insects on this suitcase?

Well, this is literally because

we're doing this for the first time during the winter period.

-Not surprisingly, um, in the winter, there are less flies around.

-Hmm.

'To contrast with what would've happened in summer,

'Martin has with him some laboratory-bred maggots

'raised in warmer conditions.'

Certainly, if it was like this during the summer,

we would have a situation like this,

where you have the tissues are very decomposed,

and you can see now, in here, some really large maggots feeding away.

What have you learned from this suitcase research?

Well, we're in the fairly early days of this research at the moment,

but our preliminary trials in the summer

indicated a delay of one-to-three days in insects gaining access

to a body in a suitcase and this first go in the winter

shows that, er, it could be at least two weeks, that delay.

'But there's still one part of the insect life cycle that can

'hamper scientists' efforts to establish time of death.'

As it transforms from maggot to fly,

a larva spends six days inside a pupa.

To see beyond this barrier,

Martin and his colleagues are using CT scanning technology

normally used to look inside the human body.

We're quite good at ageing larvae,

but the pupae themselves, all the changes go on

in an opaque, brown, rugby ball-shaped thing

and you can't see what's happening inside,

unless you actually kill them and dissect them.

The objective of all of this is to be able to age these pupae

to a much greater level of accuracy

than we've been able to do in the past.

I hope that we can improve the accuracy down to about

10% of their age, which, in the summer, would be about one day.

Prior to that, you've probably only got to

within about 2.5 days' accuracy.

So, Martin, if you were to combine the new information

that you've gathered from your research

in dating things on the suitcase with the pig's head in there,

and then this very sophisticated technology,

how could that help you assist the police in a particular crime case?

It all helps us to build up a jigsaw of evidence.

Our part of that jigsaw is to improve the timing of death.

Since the time of Buck Ruxton,

entomology has become a key part of forensic science...

..but it began with a leap of faith on the part of John Glaister.

He was a creative problem solver,

inventing and adopting new techniques

to identify the victims of crimes.

However, the killers were making innovations of their own.

Soon, forensic science would face its toughest challenge yet.

On February the 26th, 1949,

John Haigh was being questioned by police

about the disappearance of a woman - 69-year-old Olive Durand-Deacon.

Haigh was more than willing to help the police with their enquiries.

What he told them was totally unexpected.

"Mrs Durand-Deacon no longer exists.

"She has disappeared completely and no trace can ever be found.

"I have destroyed her with acid.

"Every trace has gone.

"How can YOU prove a murder if there is no body?"

Haigh went on to gleefully detail

how he'd killed Mrs Olive Durand-Deacon.

He lured her to his workshop, shot her in the back of the head

and then dumped her body in a barrel of sulphuric acid.

Three days later, when the acid had dissolved her body,

he returned and simply poured the sludge onto the ground outside.

But his sinister boasting didn't stop there.

He admitted five further murders.

After each killing,

he assumed control of his victim's financial affairs.

Haigh was a serial killer who murdered for money.

Despite his confession,

Haigh was convinced that he'd get away with all six murders.

He fancied himself as a bit of a legal expert and he knew

that the police would need more than just a confession to convict him.

This is because of an aspect of law known as Corpus Delicti,

literally meaning "body of the crime".

Now, Haigh thought that a physical corpse would be needed

to prove that a murder had taken place

and that's why he dissolved his victims' bodies in acid.

Haigh had it wrong.

In law, Corpus Delicti doesn't refer to the physical body of the victim.

It means the body of evidence

that collectively proves a crime has taken place.

Haigh wasn't as immune to prosecution as he thought.

So, somewhat bizarrely, the police were tasked with the job

of finding corroborating evidence to support Haigh's confession.

But how do you do that with nothing more than a pile of sludge?

Police called in eminent pathologist Keith Simpson.

To him, Haigh's arrogance was like a red rag to a bull.

He set out to prove that the sludge

was indeed the remains of Olive Durand-Deacon.

At the murder scene, Simpson was lead to the patch of greasy sludge

that Haigh claimed were the remains of Olive Durand-Deacon.

At first, it didn't look very promising.

But then, he had an idea.

Focusing his mind on the victim, he wondered - what, if anything,

would survive of a body after three days in an acid bath?

And then, meticulously, he began to search every inch of the ground.

Finally, he found something -

a bright red stone.

Now, to the police, this just looked like another piece of gravel,

but Simpson knew this was a key piece of evidence

that would help him convict Haigh.

What Simpson was looking for

was some part of Mrs Durand-Deacon's body

that would resist the corrosive effects of the acid.

To demonstrate Simpson's thinking,

what I've got here is two beakers of acid

and, into them, I'm going to put a couple of soluble aspirin.

One in there...

and one in here.

Now what you can immediately see is that,

while this one's fizzing away, because the acid is dissolving it,

absolutely nothing is happening inside this one, and that's because

I've coated it with a layer of fat, in this case lard.

Now, when I was at medical school,

we were taught that a fat, fertile, fair, female of 40

was the perfect candidate to get something called gallstones.

Simpson knew that Olive was overweight, elderly and sedentary,

and he thought she too

would be just the kind of person who might get them.

Just like fat, gallstones are resistant to the effects of acid.

The small, facetted red stone that he had found

wasn't just a piece of gravel, it was a human gallstone

and it was the first piece of evidence that really proved

that what had appeared like just a pile of sludge

was in fact a human body.

Convinced these were human remains,

Simpson had the mixture of sludge and dirt -

in total nearly 100kg - sent back to the laboratory to be analysed.

Sifting through the sludge like this,

they were able to find 18 fragments of human bone.

X-ray analysis showed that the fragments were fragile

even before they went in the acid, with signs of osteoarthritis.

This is a condition that's suffered by elderly people

and he knew that Olive had been 69 at the time of her disappearance.

Simpson had established the presence of human remains

and the likely age of the victim,

but could he now prove that the person in the sludge was female?

Of all the bones in the human body,

none shows the variation between the sexes more clearly than the pelvis.

I've got a female pelvis here and also a male one.

The female pelvis is broad,

to assist in childbirth,

whereas the male pelvis has got a much more

acute angle at the pubic arch and, because the man doesn't need

to have babies, it's narrow at the pelvic outlet.

Now it's pretty obvious, when you look at the differences

on this big a scale, what they are.

But all that Simpson had to go by was a tiny fragment of bone.

Fortunately, what he found in that fragment

was a section of a groove called the preauricular sulcus.

This is more marked in women than men

and, from this, Simpson was able to tell that the victim was female.

But there was a further clue to be found.

Over two stone of human fat were extracted from the sludge.

The victim was obviously portly...

..just like Olive Durand-Deacon.

From within the sludge, Simpson and his team

had managed to resurrect the figure of an overweight elderly lady,

who suffered from gallstones and arthritis,

and she had been dissolved in sulphuric acid.

Under Simpson's forensic gaze,

the sludge was revealed as a match for the missing woman.

It was enough to corroborate Haigh's confession.

John Haigh was hanged here, at Wandsworth Prison,

on the 6th of August, 1949.

The case of the Acid Bath Murderer

became a powerful advertisement for the skills of forensic scientists.

There could no longer be any doubt.

To prove a murder, you didn't need a body.

In the century between the killing of George Parkman

and the Acid Bath Murderer,

forensic science had developed into a formidable force for justice.

Murder victims now rarely stayed anonymous for long,

but identifying a killer

directly from evidence left at a crime scene

was still only possible from fingerprints.

What would change this was perhaps

the most crucial breakthrough in the history of forensic science.

It came nearly four decades after the execution of John Haigh,

on the back of a particularly harrowing case.

On the 31st of July, 1986,

the body of a schoolgirl, Dawn Ashworth,

was discovered here in a secluded area of Enderby,

a village just outside Leicester.

She'd been raped and strangled.

Almost immediately, the police named their prime suspect -

a 17-year-old boy called Richard Buckland, who'd been spotted

acting suspiciously near where Dawn's body was found

and who appeared to know details of the crime

that weren't public knowledge.

As soon as the police got him in for questioning,

he confessed to the murder,

but his confession raised a difficult question for the police.

Was he responsible for, not one murder, but two?

Three years earlier, the body of 15-year-old Lynda Mann

had been found in the nearby village of Narborough.

She'd also been raped and strangled.

Police were absolutely convinced

the same man was responsible for both murders...

..but Richard Buckland refused to confess to the earlier murder.

The police didn't have enough evidence

to directly connect Buckland to the murder of Lynda Mann,

but they did have something else -

semen samples taken from both crime scenes - and this gave them an idea.

They'd heard about a brand-new method

for establishing paternity with DNA being pioneered

by Dr Alec Jeffreys and his team at the University of Leicester.

Desperate for a break, they decided to call Dr Jeffreys

and ask him the million dollar question -

could his technology be used, not for establishing a father,

but for catching a killer?

'It was a question no-one had asked him before,

'but he was far from confident

'that his new DNA techniques would work within a police investigation.'

Well, it was out of the blue and actually quite terrifying

because we knew, in principle, we had a technology that might be

applicable to forensics, but nobody had ever done it.

-Mm-hm.

-It had never been applied in anger

in a real live murder investigation,

so I accepted to take on the case

in the full expectation of getting absolutely nothing out of it.

This was going to be a big shot in the dark.

Jeffreys and his team

were given samples taken from both crime scenes.

They analysed them using a new technique they'd developed

called DNA profiling.

This technology represented an individual's genetic code

as a two-band pattern.

It may look simple, but the chances of two unrelated people

having the same profile are millions to one.

The entire case would rest on this ground-breaking work.

These are the original set of DNA profiles from this case,

so, if we look through here, this is the first victim

-and what you see here is a two-band DNA profile.

-So this is Lynda Mann,

-who was the first girl that was murdered?

-That's correct, yes, yeah.

'This second track was made with a sample

'taken from Lynda's body after she'd been raped.

'Again, her own DNA profile is clearly visible,

'but this time, it's not the only one.'

But you also see another two bands up here,

which must be the DNA profile of the semen from the assailant.

We now move to the second victim.

-So Dawn Ashworth?

-Dawn Ashworth.

-Yeah.

-So, you see her DNA profile -

-completely different from this profile...

-Yes.

-..and that profile.

'This profile here was obtained

'from small amounts of semen recovered alongside Dawn's body.'

If one looks very carefully, there's trace amounts of semen in there.

You can see a two-band DNA profile there, that doesn't match the victim,

so it must be from the perpetrator and, much more importantly,

that profile seems to match the profile of the first victim.

The police were right -

the same man had committed both murders -

but there was a problem.

The DNA profile of their prime suspect, Richard Buckland,

didn't match the unknown assailant.

He couldn't be the killer of Dawn Ashworth and Lynda Mann.

This is a really important point,

that the first time DNA was ever used in anger in a criminal investigation

was not to establish guilt, it was to establish innocence.

And I think, given this young man's confession

and some circumstantial evidence surrounding the case,

my guess, he would've been found guilty

and jailed for the rest of his life for those offences,

and the true perpetrator would've been left free to carry on offending.

Richard Buckland became the first person in history

to be exonerated on the basis of DNA...

..but that meant the killer was still out there.

Police realised that, if DNA could be used to prove innocence,

it could also be used to establish guilt,

and they embarked on the world's first-ever DNA manhunt.

The police were convinced that the murderer was a local man.

Over 5,000 men in the area had blood and saliva samples taken

and a DNA profile was established for each and every one of them.

The whole process took more than six months

and was known by the press as The Blooding.

But not a single profile matched the samples

recovered from Dawn Ashworth and Lynda Mann.

It looked as if the murderer had got away scot-free.

MUSIC: True Faith by New Order

Now the police were in desperate need of a break.

In August 1987, a group of bakery workers

were enjoying a lunchtime drink when one of them,

Ian Kelly, started to tell an interesting story about the case.

He described how he'd been approached by another one of

their colleagues, Colin Pitchfork, with a very strange proposition.

Pitchfork said that he'd already given a blood sample

to the police to cover for a friend of his

who was a bit worried he might be framed for the murders,

and now he, Pitchfork, was concerned that he

was going to get into trouble for this small act of kindness.

On the basis of his plea, and for a small amount of £200,

Ian Kelly had agreed to take the DNA test for him.

Listening to this story was a female bakery worker,

who was very concerned by what she heard,

and her concerns preyed on her mind for weeks

until eventually she took them to the police.

This was the breakthrough they'd been looking for.

Colin Pitchfork, a local 27-year-old baker,

was swiftly arrested.

A sample of his DNA was sent for analysis.

Having got the wrong man first-time round, obviously there was

a slight concern they'd got the wrong person second-time round,

so it was a big relief when the phone call came through and said,

"Yes, we've got a full DNA match...

"with semen from both of these victims.

"This is definitely your man."

On the 22nd of January, 1988,

Colin Pitchfork was convicted of the murders of Dawn Ashworth

and Lynda Mann,

and sentenced to life imprisonment.

He became the first person ever to be convicted of murder

on the basis of genetic evidence.

Nearly 30 years after this pivotal case,

we're now on the verge of another revolution in forensic DNA analysis.

Scientists are attempting something that was once thought impossible -

to recreate a face from DNA.

It's called Molecular Photofitting and though it

sounds like science fiction, it could soon be a forensic reality.

I'm on my way to Belgium to meet a team of researchers

who believe they could make it happen.

If they succeed,

the face of a killer could be obtained directly from DNA

left at a crime scene and, today,

I'm playing the part of the criminal.

Eight weeks ago, DNA was extracted from my saliva

and the results sent anonymously to a group of scientists.

They're now using that data to build a picture of my face

as predicted by my genes.

The question is - will it look anything like me?

I'm curious to arrive in Belgium now.

It could be because I was just rubbish at genetics

at medical school and never really understood how it all worked.

I just fail to understand how someone could take

a sample of my saliva and turn that into a picture of me.

I'm meeting Dr Peter Claes,

a medical-imaging specialist at the University of Leuven.

Along with colleagues in the USA,

he has built up a database of faces and DNA.

Armed with this, he's able to model how a face is constructed

based on just 20 genes.

I know that, eight weeks ago, he was sent a sample of my DNA

from my saliva and now the moment has arrived

when I'm going to go into this room

and see if the face, the model of the face that he's come up with

purely on the base of my spit, looks anything like me.

Gosh, is that really me?

I can see the eyes are my eye colour and...does it look like me, Peter?

I think it does in several aspects.

I can tell you that your eyebrows are indeed sticking more...

forward more and your chin as well,

so you have a very prominent, specific chin compared to

an average European female,

which is, in my eyes, not a bad result.

You have very flat cheeks but, of course, that's a tricky area

to actually predict accurately because it's heavily influenced

by your diet, which is an environmental factor.

The nose could have been better.

And, in fact, I broke my nose when I was younger,

so that might explain why the nose doesn't exactly match.

Exactly, it's an environmental effect on your face,

which is clearly not coded in your DNA

and hence it was not revealed by the prediction.

If we superimpose this predicted face over a photo,

the accuracy of the technique is revealed

and seeing this likeness of me is truly uncanny.

The eyes, nose, mouth and chin are all roughly in the right place,

but the features are more rounded than in reality.

Police couldn't publish a Molecular Photofit like this

and hope to catch a killer...

..but that's not how Peter sees the technique being used

in a criminal investigation.

If I would bring this result to an investigator,

I wouldn't necessarily give him the image to be broadcast,

I would talk to him and say, "OK, what you're looking for is

"indeed a European female, but with particular eyebrows and chin."

That information is already of high value because it can focus

the investigation on looking for such a person.

This may be new science,

but Peter and his colleagues are rapidly developing the technology.

The number of genes used is being expanded from 20...

to 200.

Molecular Photofitting is only going to become

more accurate in the coming years.

And, as we've seen from history, all it will take is one case,

one key breakthrough,

to establish it on the forensic stage.

Next time, crime scenes.

I'll discover how mud can catch a killer,

I'll try to make sense of blood-spatter patterns

and I'll scrutinise the single thumb print that hanged two men.

Delve deeper with the Open University

and find out more about the science behind forensics.

Go to...

..and follow the links to the Open University.