A Question of Identity

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0:00:04 > 0:00:06In the act of murder,

0:00:06 > 0:00:11there is a weapon...

0:00:11 > 0:00:16a crime scene...

0:00:16 > 0:00:19and a body -

0:00:19 > 0:00:20all vital evidence

0:00:20 > 0:00:23in the hunt for the killer.

0:00:25 > 0:00:27It's a game of cat and mouse

0:00:27 > 0:00:29between police and murderer

0:00:29 > 0:00:32that used to favour the criminal,

0:00:32 > 0:00:33but then something happened

0:00:33 > 0:00:37that swung the odds in favour of justice...

0:00:39 > 0:00:42..the arrival of forensic science.

0:00:47 > 0:00:49I'm Gabriel Weston.

0:00:49 > 0:00:53As a surgeon and writer, I'm fascinated by the work

0:00:53 > 0:00:58of the forensic scientist and the murders they've helped to solve.

0:01:02 > 0:01:05In this series,

0:01:05 > 0:01:11I'll explore the cases that transformed criminal investigation,

0:01:11 > 0:01:15through poison and acid...

0:01:15 > 0:01:17fingerprints and blood.

0:01:19 > 0:01:21From the earliest days

0:01:21 > 0:01:25to the cutting edge of modern forensics.

0:01:27 > 0:01:29There will always be those who believe

0:01:29 > 0:01:32they can commit the perfect murder,

0:01:32 > 0:01:36who think they can conceal their victim's identity

0:01:36 > 0:01:38as well as their own,

0:01:38 > 0:01:42but forensic science has emerged as a formidable force

0:01:42 > 0:01:46to challenge the killers and bring them to justice.

0:02:01 > 0:02:07The history of crime is full of anonymous corpses -

0:02:07 > 0:02:11bodies mutilated to the point where identification

0:02:11 > 0:02:13was simply impossible.

0:02:16 > 0:02:20They are the murders where the body itself presented

0:02:20 > 0:02:24the main challenge to investigators and, as a surgeon,

0:02:24 > 0:02:28they're the cases that I'm naturally most interested in because

0:02:28 > 0:02:33they're the ones that could only be solved using medical expertise.

0:02:37 > 0:02:40I'm going to trace the rise of forensic science

0:02:40 > 0:02:44through four breakthrough cases,

0:02:44 > 0:02:48from charred bones to DNA -

0:02:48 > 0:02:51all questions of identity.

0:02:54 > 0:02:58The first began here, at Harvard Medical College, Boston,

0:02:58 > 0:03:02on November the 25th, 1849.

0:03:06 > 0:03:12Inside one of the laboratories, George Parkman lay dead...

0:03:12 > 0:03:14murdered...

0:03:14 > 0:03:17by Professor John White Webster.

0:03:23 > 0:03:26In a heated argument over unpaid debts,

0:03:26 > 0:03:29Webster struck Parkman over the head...

0:03:31 > 0:03:34..killing him outright.

0:03:34 > 0:03:38Webster suddenly had more than money to worry about.

0:03:38 > 0:03:40He was now a killer.

0:03:50 > 0:03:54Webster had little time to cover his tracks.

0:03:54 > 0:03:57His victim was no ordinary member of the public.

0:04:02 > 0:04:05George Parkman was a man of considerable standing

0:04:05 > 0:04:08within Boston society.

0:04:08 > 0:04:13As a respected Harvard academic, moneylender and landowner,

0:04:13 > 0:04:15he was well-known across the city,

0:04:15 > 0:04:19so his disappearance was quickly reported to the police.

0:04:20 > 0:04:26The authorities embarked on a huge citywide hunt for the missing man.

0:04:26 > 0:04:29Even the river and Boston Harbour were dredged,

0:04:29 > 0:04:34but there were no signs of George Parkman to be found.

0:04:34 > 0:04:37Somehow, Professor Webster had managed to make

0:04:37 > 0:04:40the body of his victim simply vanish.

0:04:43 > 0:04:46The city was buzzing with many wild theories of what

0:04:46 > 0:04:49might have befallen George Parkman,

0:04:49 > 0:04:53but one man alone suspected the truth.

0:04:53 > 0:04:58Ephraim Littlefield, a janitor at the Harvard Medical College,

0:04:58 > 0:05:01had witnessed Parkman entering the building,

0:05:01 > 0:05:04but never saw him leave,

0:05:04 > 0:05:09and now Professor Webster was acting out of character.

0:05:09 > 0:05:14His laboratory door, usually open, was locked.

0:05:14 > 0:05:17FIRE ROARS

0:05:17 > 0:05:19From beneath the door,

0:05:19 > 0:05:24Ephraim Littlefield saw Webster making repeated visits to the

0:05:24 > 0:05:28laboratory furnace and a terrible question grew in his mind.

0:05:30 > 0:05:34If Webster wanted to conceal a body, where would he hide it?

0:05:35 > 0:05:39As a janitor, Littlefield knew every inch of the college...

0:05:45 > 0:05:47..and taking matters into his own hands,

0:05:47 > 0:05:49he broke into a sealed vault

0:05:49 > 0:05:52connected to Webster's laboratory toilet...

0:05:55 > 0:05:58..and there he discovered human remains.

0:06:02 > 0:06:07Thanks to Ephraim Littlefield, the police had a body on their hands.

0:06:10 > 0:06:12The vault underneath Webster's toilet

0:06:12 > 0:06:17was full of hacked-up limbs and, locked inside a chest in his lab,

0:06:17 > 0:06:22they found a whole torso with a left thigh stuffed inside it.

0:06:24 > 0:06:28All the circumstances pointed to it being George Parkman...

0:06:30 > 0:06:34..and now Professor John White Webster was

0:06:34 > 0:06:37arrested on suspicion of his murder.

0:06:40 > 0:06:43Police recovered almost a complete body from

0:06:43 > 0:06:45in and around Webster's laboratory.

0:06:48 > 0:06:51The head, however, was missing and this was crucial.

0:06:53 > 0:06:57Without it, they would struggle to identify the body.

0:07:02 > 0:07:06But once again, the janitor Littlefield led the way.

0:07:06 > 0:07:09He showed them to the laboratory furnace.

0:07:12 > 0:07:16Inside were the cremated ashes of a human head.

0:07:18 > 0:07:22This was Webster's attempt to obliterate the identity

0:07:22 > 0:07:23of George Parkman...

0:07:27 > 0:07:33..but destroying a skull is a far harder task than Webster realised.

0:07:39 > 0:07:44To demonstrate, I'm going to recreate the grisly affair.

0:07:46 > 0:07:49This is a sheep skull.

0:07:49 > 0:07:50It's not a human skull,

0:07:50 > 0:07:53but in terms of hardness and density,

0:07:53 > 0:07:55it's remarkably similar,

0:07:55 > 0:07:59and I've come to this amazing incineration unit

0:07:59 > 0:08:03to see what happens when we put this skull in the furnace.

0:08:05 > 0:08:08MACHINE WHIRS

0:08:13 > 0:08:17This incinerator is used to cremate animal carcasses

0:08:17 > 0:08:23and can reach temperatures in excess of 1,000 degrees Celsius,

0:08:23 > 0:08:27and the skull is going to spend several hours inside.

0:08:29 > 0:08:33I'm curious to see how much will remain.

0:08:38 > 0:08:40I expected I'd have a pile of ashes here

0:08:40 > 0:08:44but in fact, it looks very much as it did before.

0:08:44 > 0:08:47Now, in these circumstances, what usually happens is that

0:08:47 > 0:08:51the bony remains are put through something called a cremulator,

0:08:51 > 0:08:55which grinds them up into what we would think ashes look like,

0:08:55 > 0:08:58and what I'm going to do now is try and mimic that process

0:08:58 > 0:09:03with this hammer, and see if I can destroy what's left of this skull.

0:09:08 > 0:09:12Now, that's what Parkman's killer would have had to do...

0:09:14 > 0:09:17..but Webster failed to complete the job.

0:09:20 > 0:09:27Inside his laboratory furnace was a partial jawbone and some teeth...

0:09:33 > 0:09:36..and it was these tiny fragments of a human being

0:09:36 > 0:09:40that would completely change the course of forensic science.

0:09:46 > 0:09:49The 19th century saw the emergence of dentistry

0:09:49 > 0:09:51as a respected branch of medicine.

0:09:53 > 0:09:58Bad teeth could now easily be replaced by dentures.

0:10:00 > 0:10:03In making these, dentists kept accurate models

0:10:03 > 0:10:06of their patients' jaws and teeth -

0:10:06 > 0:10:08in other words, dental records.

0:10:10 > 0:10:13And in a stroke of luck for detectives,

0:10:13 > 0:10:16George Parkman had bad teeth.

0:10:19 > 0:10:23His dentist, Dr Nathan Keep, had crafted him

0:10:23 > 0:10:25an ornate set of dentures.

0:10:31 > 0:10:33Rachel Bairstow is curator

0:10:33 > 0:10:36at the Museum of the British Dental Association.

0:10:40 > 0:10:45Parkman's dentures would have been made by taking a beeswax impression

0:10:45 > 0:10:49of the mouth and then a plaster cast would have been

0:10:49 > 0:10:52taken of that, and it was likely that he had

0:10:52 > 0:10:56a metal denture of some sort, with some porcelain teeth attached.

0:10:58 > 0:11:00You can see the clasps here,

0:11:00 > 0:11:03This is how it anchored into place around existing teeth,

0:11:03 > 0:11:06so it made a very good fit.

0:11:06 > 0:11:07The craftsmanship was amazing, you know,

0:11:07 > 0:11:11hammered into place by hand,

0:11:11 > 0:11:13- to get the best that you could at that time.- Yeah.

0:11:13 > 0:11:16It would have been a very unique set.

0:11:22 > 0:11:26Webster's trial began on the 19th of March, 1850.

0:11:28 > 0:11:31When dentist Dr Nathan Keep took the stand,

0:11:31 > 0:11:35he had with him his models of Parkman's jaw and denture...

0:11:37 > 0:11:42..and also the fragments of bone found in the laboratory furnace.

0:11:44 > 0:11:47So what did Keep do in the court of law?

0:11:47 > 0:11:50So, he would have brought in the plaster cast model that he had

0:11:50 > 0:11:53and this is the point where it would have been married up with

0:11:53 > 0:11:57the items that were found, so the jawbone and the teeth.

0:11:57 > 0:12:01The teeth would have been inserted into the jawbone

0:12:01 > 0:12:06and then the denture plate would have been inserted over the top.

0:12:06 > 0:12:10The jury can have had no doubt that this was Parkman in the furnace.

0:12:15 > 0:12:19This was the legal birth of forensic dentistry.

0:12:20 > 0:12:23On the basis of the dentist's testimony,

0:12:23 > 0:12:27the remains were confirmed as belonging to George Parkman.

0:12:29 > 0:12:32The janitor Littlefield collected a 3,000 reward

0:12:32 > 0:12:34for his efforts...

0:12:36 > 0:12:40..and John White Webster was sentenced to death.

0:12:49 > 0:12:51SIREN WAILS

0:12:53 > 0:12:56Today, forensic dentists are called upon

0:12:56 > 0:13:01in the most tragic of circumstances -

0:13:01 > 0:13:05in situations where only dental records can confirm

0:13:05 > 0:13:08the identity of the dead -

0:13:08 > 0:13:11but dentistry can do more than just identify

0:13:11 > 0:13:13the victims of crime or disaster.

0:13:15 > 0:13:18Here at the University of Cardiff Dental Hospital,

0:13:18 > 0:13:23forensic scientists are turning their attention toward the criminal.

0:13:25 > 0:13:29It's not unusual for a killer to leave bite marks on their victim

0:13:29 > 0:13:33and these can be used as evidence in murder cases.

0:13:33 > 0:13:36The idea is that if you can marry the bite marks to the teeth

0:13:36 > 0:13:40that made them, you can catch the killer,

0:13:40 > 0:13:43but recently in the USA, certain convictions that were secured

0:13:43 > 0:13:47using this kind of evidence have been overturned

0:13:47 > 0:13:50and the whole reliability of bite mark analysis

0:13:50 > 0:13:52called into question.

0:13:58 > 0:13:59To demonstrate why,

0:13:59 > 0:14:03I'm leaving some bite marks of my own on this clay arm

0:14:03 > 0:14:08and taking it to forensic dentist Romina Carabott for analysis.

0:14:10 > 0:14:14So, first of all, we've got different pressure that has been applied,

0:14:14 > 0:14:17so some of them have gone quite deep, whereas others,

0:14:17 > 0:14:22like what we've got here, have stayed on the surface of the clay.

0:14:22 > 0:14:26We've also got a curved surface here and that will affect

0:14:26 > 0:14:29the shape of the print that the tooth would leave.

0:14:31 > 0:14:33To analyse bite marks,

0:14:33 > 0:14:38forensic dentists take high-resolution photographs,

0:14:38 > 0:14:40but a 2-D image doesn't represent

0:14:40 > 0:14:43a three-dimensional surface accurately,

0:14:43 > 0:14:46so getting precise measurements from a curved body part -

0:14:46 > 0:14:49like an arm - is difficult.

0:14:49 > 0:14:52It's further complicated by the skin itself,

0:14:52 > 0:14:55which swells and bruises around the mark.

0:14:57 > 0:15:01Combined, these factors can make it extremely difficult

0:15:01 > 0:15:04to make an accurate bite mark analysis...

0:15:07 > 0:15:10..and that's what makes this type of evidence easy to

0:15:10 > 0:15:12question in a court of law,

0:15:12 > 0:15:17but imaging specialist Sam Evans is working with Romina to

0:15:17 > 0:15:20develop a new 3-D technique that could provide

0:15:20 > 0:15:23a more accurate way of measuring bite marks.

0:15:26 > 0:15:31This is a modified SLR camera, with a stereoscopic lens

0:15:31 > 0:15:34on the front that takes a pair of images,

0:15:34 > 0:15:38so then software that's designed specifically for this camera

0:15:38 > 0:15:40can create 3-D images.

0:15:40 > 0:15:42CAMERA SHUTTER CLICKS

0:15:42 > 0:15:45Sam feeds his photos into specialist imaging software

0:15:45 > 0:15:49that produces a 3-D model.

0:15:49 > 0:15:53This means the bite mark can be analysed much more accurately

0:15:53 > 0:15:54than with a simple photo.

0:15:57 > 0:15:59What are we looking at here, Romina?

0:15:59 > 0:16:03The software has constructed the curvature of the arm

0:16:03 > 0:16:07with the bite mark on it and so now we can rotate it around

0:16:07 > 0:16:11and we can analyse each different part of the arm.

0:16:11 > 0:16:13When you're actually using this technology,

0:16:13 > 0:16:18how do you measure the tooth to see if the tooth fits the bite?

0:16:18 > 0:16:21Say, for example, I want to take a measurement of the width

0:16:21 > 0:16:25of the arch, the distance between the mark of the left canine and the

0:16:25 > 0:16:30right canine, then we're going to just draw a line there and, because

0:16:30 > 0:16:34the camera is calibrated together with the software, it facilitates

0:16:34 > 0:16:37and increases the chances that I am going to be as accurate -

0:16:37 > 0:16:41as precise, rather - as possible in my conclusions and analysis.

0:16:43 > 0:16:48This work shows how forensic science is constantly seeking

0:16:48 > 0:16:51new ways to establish identity.

0:16:51 > 0:16:55It's long been a defining characteristic of the field.

0:16:58 > 0:17:01After the murder of George Parkman in 1850,

0:17:01 > 0:17:03new forensic techniques emerged,

0:17:03 > 0:17:07and with them, a new breed of scientist -

0:17:07 > 0:17:09the forensic pathologist.

0:17:13 > 0:17:17They used their knowledge of human anatomy to help solve crime.

0:17:18 > 0:17:23Killers now had to go to extreme lengths to obscure

0:17:23 > 0:17:25the identity of their victims.

0:17:31 > 0:17:36This area, just a few miles north of the Scottish border town of Moffat,

0:17:36 > 0:17:38is known as the Devil's Beef Tub.

0:17:40 > 0:17:43It's a place of outstanding natural beauty,

0:17:43 > 0:17:46but it also has a dark and grisly past.

0:17:46 > 0:17:49On September 29th, 1935,

0:17:49 > 0:17:53two women were walking exactly where I have been now

0:17:53 > 0:17:56and, as they crossed the bridge, one of them happened to look down

0:17:56 > 0:18:00and she saw something very strange in the ravine below.

0:18:03 > 0:18:07The stream was littered with discarded parcels.

0:18:08 > 0:18:13Looking closer, she saw something horrific...

0:18:13 > 0:18:14a human arm.

0:18:18 > 0:18:21When police arrived, an even grimmer picture emerged.

0:18:25 > 0:18:28More bundles were discovered -

0:18:28 > 0:18:32each contained decomposing human remains.

0:18:37 > 0:18:4218 body parts, as well as assorted fragments of bone and tissue,

0:18:42 > 0:18:44were found up and down this stream.

0:18:46 > 0:18:49Some had been wrapped in paper,

0:18:49 > 0:18:51some were just lying in the water.

0:18:52 > 0:18:56The remains were mutilated beyond recognition -

0:18:56 > 0:18:58it wasn't even possible to tell

0:18:58 > 0:19:01how many victims there were at the scene.

0:19:05 > 0:19:07Forensic pathologists from Glasgow

0:19:07 > 0:19:10and Edinburgh Universities were called in.

0:19:11 > 0:19:14They were led by Professor John Glaister Jr.

0:19:17 > 0:19:23To their expert eyes, the jigsaw of body parts started to tell a story.

0:19:23 > 0:19:26It was clear that the murderer had gone to great lengths to

0:19:26 > 0:19:30remove all traces of identity from their victims.

0:19:30 > 0:19:34Fingertips had been carefully dissected out at the joint.

0:19:34 > 0:19:39Teeth had been pulled from the upper jaw without doing any damage to

0:19:39 > 0:19:41the surrounding bone,

0:19:41 > 0:19:44which suggested the expert use of dental pliers.

0:19:46 > 0:19:50They knew they were dealing with a murderer who probably had

0:19:50 > 0:19:53medical training.

0:19:53 > 0:19:56But who were the victims and who had killed them?

0:20:00 > 0:20:04The remains were sent to Edinburgh University, where a team

0:20:04 > 0:20:08headed up by Glaister, and college Professor James Brash,

0:20:08 > 0:20:11set about reconstructing the victims.

0:20:13 > 0:20:16It was a monumental challenge.

0:20:17 > 0:20:20Painstakingly sifting through the remains,

0:20:20 > 0:20:23they established there were two victims...

0:20:27 > 0:20:28..both female.

0:20:30 > 0:20:33One six inches taller than the other.

0:20:37 > 0:20:43Analysing the skulls, they revealed a further critical detail.

0:20:43 > 0:20:45These lines look like cracks,

0:20:45 > 0:20:49but they're actually joints called sutures

0:20:49 > 0:20:50and they enable the skull

0:20:50 > 0:20:57and the brain to grow as we age, and they don't fuse until about 40.

0:20:57 > 0:21:03Now over here, we've got an X-ray of the skulls found at the scene.

0:21:03 > 0:21:07The one here has got the suture lines almost fused,

0:21:07 > 0:21:10which means that this would have belonged to somebody

0:21:10 > 0:21:15in their mid-to-late 30s, and this compares quite noticeably with

0:21:15 > 0:21:20the one on the other side, where the suture line is quite noticeably

0:21:20 > 0:21:24open still, and would have belonged to somebody in their early 20s.

0:21:27 > 0:21:30The suture marks in the skulls told Glaister and Brash

0:21:30 > 0:21:32how old the victims were.

0:21:35 > 0:21:37While they continued to analyse the remains,

0:21:37 > 0:21:41the police carried out more conventional detective work...

0:21:42 > 0:21:44..and they had a lead.

0:21:46 > 0:21:51One of the bundles was wrapped in pages from the Sunday Graphic.

0:21:51 > 0:21:53It was a special edition,

0:21:53 > 0:21:57only available in the Morecambe and Lancaster district,

0:21:57 > 0:22:02and a young woman had recently been reported missing in that area.

0:22:09 > 0:22:14The missing person was 20-year-old Mary Rogerson.

0:22:14 > 0:22:20She worked as a live-in nursemaid for Isabella Ruxton, in Lancaster.

0:22:22 > 0:22:28The thing was that 34-year-old Isabella had also disappeared.

0:22:28 > 0:22:32Both missing women lived at number two Dalton Square

0:22:32 > 0:22:34with Isabella's common-law husband,

0:22:34 > 0:22:36a Dr Buck Ruxton.

0:22:40 > 0:22:44Ruxton was a respected GP in Lancaster,

0:22:44 > 0:22:48but beneath this veneer lurked a paranoid personality.

0:22:51 > 0:22:53He'd been reported to police on two previous occasions

0:22:53 > 0:22:56for threatening to kill his wife...

0:22:57 > 0:23:02..and neither his wife Isabella nor the maid Mary had been seen

0:23:02 > 0:23:03since the 14th of September.

0:23:05 > 0:23:12A search of the house at two Dalton Square raised serious concerns.

0:23:12 > 0:23:15Clothing and carpets had been burned in the back yard.

0:23:16 > 0:23:19Blood stains were found in the bathroom.

0:23:20 > 0:23:26It was enough for police to question Buck Ruxton on suspicion of murder.

0:23:32 > 0:23:35The similarities between the missing women

0:23:35 > 0:23:38and the corpses in the mortuary were striking.

0:23:38 > 0:23:42Both women were precisely the right age

0:23:42 > 0:23:46and Isabella was even six inches taller than Mary.

0:23:46 > 0:23:51But in the cold light of day, these were just similarities,

0:23:51 > 0:23:56hardly the kind of hard evidence necessary to establish

0:23:56 > 0:23:59identity or even guilt.

0:23:59 > 0:24:03Ruxton himself claimed he'd never even been to Moffat,

0:24:03 > 0:24:06but then Glaister had an idea.

0:24:10 > 0:24:14He obtained recent photos of Isabella and Mary,

0:24:14 > 0:24:17then he took the skulls recovered from the stream

0:24:17 > 0:24:21and photographed them using the same camera

0:24:21 > 0:24:24and from precisely the same angle.

0:24:26 > 0:24:30What he did next was a stroke of genius.

0:24:32 > 0:24:34He took the original photo

0:24:34 > 0:24:39and superimposed it over his own macabre recreation.

0:24:43 > 0:24:45And the result is astonishing.

0:24:49 > 0:24:51It's almost like an X-ray.

0:24:53 > 0:24:58You can see the dead skull peering out from behind the living picture.

0:25:01 > 0:25:04The angle of the jaw is perfectly in line,

0:25:04 > 0:25:07the orbit of the eye is in the right position.

0:25:07 > 0:25:09The bridge of the nose is perfect.

0:25:12 > 0:25:16Glaister and Brash were absolutely sure that the missing women

0:25:16 > 0:25:18were the corpses in the mortuary.

0:25:21 > 0:25:25Eventually another body part was found -

0:25:25 > 0:25:29a forearm with the fingertips intact.

0:25:29 > 0:25:33The prints matched those taken from Mary Rogerson's room

0:25:33 > 0:25:36at two Dalton Square.

0:25:36 > 0:25:40The identity of the victims now seemed beyond doubt,

0:25:40 > 0:25:43but there was one more key piece of evidence

0:25:43 > 0:25:45that would point to the killer.

0:25:47 > 0:25:52In any murder case, establishing the time of death is vital.

0:25:52 > 0:25:57It can help link the murderer to the victim and, in the 1930s,

0:25:57 > 0:26:02an area of science was about to enter the forensic realm

0:26:02 > 0:26:06that would make estimating time of death much more accurate.

0:26:11 > 0:26:14When the body parts were discovered,

0:26:14 > 0:26:18they were decomposing and riddled with maggots.

0:26:18 > 0:26:23But Glaister didn't just dispose of these, he preserved them.

0:26:23 > 0:26:25These are the actual maggots

0:26:25 > 0:26:28recovered from the remains of Isabella.

0:26:30 > 0:26:35Glaister took them to Dr Alexander Mearns at Glasgow University.

0:26:35 > 0:26:40He was an expert in entomology, the study of insects.

0:26:40 > 0:26:44From the state of the bodies, it had been estimated that the victims

0:26:44 > 0:26:48died around the 19th of September,

0:26:48 > 0:26:51but the maggots told a different story.

0:26:52 > 0:26:55Using his expertise,

0:26:55 > 0:26:59Mearns was able to deduce that the maggots had been hatched from eggs

0:26:59 > 0:27:04laid by a bluebottle 12 days before the remains were discovered,

0:27:04 > 0:27:08so death must have occurred around the 15th of September.

0:27:11 > 0:27:15It was close to the last time that Isabella was seen alive

0:27:15 > 0:27:19in Lancaster, just before entering the house

0:27:19 > 0:27:22she shared with Buck Ruxton.

0:27:25 > 0:27:27Police were convinced that Ruxton killed his wife

0:27:27 > 0:27:30late on the 14th of September.

0:27:32 > 0:27:35The act was witnessed by the unfortunate maid Mary,

0:27:35 > 0:27:38so she too had to die.

0:27:40 > 0:27:44He dismembered both bodies in the bathroom,

0:27:44 > 0:27:49a fact confirmed when human flesh was found within the plumbing.

0:27:49 > 0:27:53He then drove to Moffat and dumped the remains,

0:27:53 > 0:27:56where they would be discovered two weeks later.

0:28:01 > 0:28:06Ruxton's trial took place on 2nd March 1936

0:28:06 > 0:28:09and science took centre stage.

0:28:09 > 0:28:13Each and every discovery was laid out for the jury in the most

0:28:13 > 0:28:17extensive display of forensic evidence ever seen

0:28:17 > 0:28:18in the British courts

0:28:18 > 0:28:24and it destroyed any hope Ruxton may have had of being found not guilty.

0:28:27 > 0:28:32At the end of the 11-day trial, the jury were in no doubt.

0:28:32 > 0:28:36The two bodies found in this stream were Mary and Isabella

0:28:36 > 0:28:39and Ruxton had killed them.

0:28:39 > 0:28:41He was sentenced to death.

0:28:53 > 0:28:57It was the first time entomology had been used as part of a murder

0:28:57 > 0:29:00investigation in the UK.

0:29:00 > 0:29:04Today, it's often the only way to estimate the time of death.

0:29:05 > 0:29:09Knowing when an insect began to lay eggs on a corpse

0:29:09 > 0:29:11allows investigators to establish

0:29:11 > 0:29:15the minimum length of time since a murder occurred.

0:29:18 > 0:29:21Dr Martin Hall is a forensic entomologist

0:29:21 > 0:29:24at the Natural History Museum.

0:29:24 > 0:29:30He's assisted the police in over 150 cases, most of them murders.

0:29:35 > 0:29:37He's conducting new research

0:29:37 > 0:29:40to increase the accuracy of the technique.

0:29:42 > 0:29:43Oh! So...

0:29:43 > 0:29:46- Not a very pretty sight. - Oh, what a sight. No!

0:29:46 > 0:29:48- No, it's not.- But, um...

0:29:48 > 0:29:50Martin, just very broadly speaking,

0:29:50 > 0:29:54why do you have a pig's head in a suitcase out here?

0:29:54 > 0:29:55It might seem a bit bizarre,

0:29:55 > 0:29:58but what we're trying to do is to work out

0:29:58 > 0:30:02what effect a body being disposed in a suitcase has

0:30:02 > 0:30:05on the insect fauna attracted to it.

0:30:07 > 0:30:09A postmortem is due to take place this afternoon

0:30:09 > 0:30:12after a women's body was found in a suitcase.

0:30:13 > 0:30:16A number of recent murder enquiries have begun

0:30:16 > 0:30:20with the discovery of a body inside a suitcase.

0:30:20 > 0:30:24Martin hopes his research can reveal how this method of disposal

0:30:24 > 0:30:28affects his calculations of the time of death,

0:30:28 > 0:30:32as a fly can't lay eggs directly on a body

0:30:32 > 0:30:34if it's locked behind such a barrier.

0:30:35 > 0:30:37He has observed how, instead,

0:30:37 > 0:30:42eggs are laid around zips and small holes.

0:30:42 > 0:30:47The maggots squeeze their way in through these tiny spaces.

0:30:47 > 0:30:49Martin's testing how quickly this happens

0:30:49 > 0:30:52in different temperature conditions.

0:30:54 > 0:30:57Why aren't there very many insects on this suitcase?

0:30:57 > 0:30:59Well, this is literally because

0:30:59 > 0:31:02we're doing this for the first time during the winter period.

0:31:02 > 0:31:06- Not surprisingly, um, in the winter, there are less flies around.- Hmm.

0:31:07 > 0:31:10'To contrast with what would've happened in summer,

0:31:10 > 0:31:13'Martin has with him some laboratory-bred maggots

0:31:13 > 0:31:16'raised in warmer conditions.'

0:31:17 > 0:31:20Certainly, if it was like this during the summer,

0:31:20 > 0:31:22we would have a situation like this,

0:31:22 > 0:31:25where you have the tissues are very decomposed,

0:31:25 > 0:31:31and you can see now, in here, some really large maggots feeding away.

0:31:32 > 0:31:35What have you learned from this suitcase research?

0:31:35 > 0:31:38Well, we're in the fairly early days of this research at the moment,

0:31:38 > 0:31:41but our preliminary trials in the summer

0:31:41 > 0:31:45indicated a delay of one-to-three days in insects gaining access

0:31:45 > 0:31:48to a body in a suitcase and this first go in the winter

0:31:48 > 0:31:51shows that, er, it could be at least two weeks, that delay.

0:31:54 > 0:31:58'But there's still one part of the insect life cycle that can

0:31:58 > 0:32:01'hamper scientists' efforts to establish time of death.'

0:32:04 > 0:32:07As it transforms from maggot to fly,

0:32:07 > 0:32:11a larva spends six days inside a pupa.

0:32:13 > 0:32:15To see beyond this barrier,

0:32:15 > 0:32:19Martin and his colleagues are using CT scanning technology

0:32:19 > 0:32:23normally used to look inside the human body.

0:32:24 > 0:32:27We're quite good at ageing larvae,

0:32:27 > 0:32:29but the pupae themselves, all the changes go on

0:32:29 > 0:32:33in an opaque, brown, rugby ball-shaped thing

0:32:33 > 0:32:35and you can't see what's happening inside,

0:32:35 > 0:32:37unless you actually kill them and dissect them.

0:32:37 > 0:32:41The objective of all of this is to be able to age these pupae

0:32:41 > 0:32:43to a much greater level of accuracy

0:32:43 > 0:32:45than we've been able to do in the past.

0:32:45 > 0:32:49I hope that we can improve the accuracy down to about

0:32:49 > 0:32:5310% of their age, which, in the summer, would be about one day.

0:32:53 > 0:32:55Prior to that, you've probably only got to

0:32:55 > 0:32:57within about 2.5 days' accuracy.

0:32:57 > 0:33:02So, Martin, if you were to combine the new information

0:33:02 > 0:33:04that you've gathered from your research

0:33:04 > 0:33:08in dating things on the suitcase with the pig's head in there,

0:33:08 > 0:33:11and then this very sophisticated technology,

0:33:11 > 0:33:16how could that help you assist the police in a particular crime case?

0:33:16 > 0:33:20It all helps us to build up a jigsaw of evidence.

0:33:20 > 0:33:25Our part of that jigsaw is to improve the timing of death.

0:33:29 > 0:33:32Since the time of Buck Ruxton,

0:33:32 > 0:33:36entomology has become a key part of forensic science...

0:33:38 > 0:33:41..but it began with a leap of faith on the part of John Glaister.

0:33:43 > 0:33:45He was a creative problem solver,

0:33:45 > 0:33:48inventing and adopting new techniques

0:33:48 > 0:33:51to identify the victims of crimes.

0:33:52 > 0:33:57However, the killers were making innovations of their own.

0:33:59 > 0:34:04Soon, forensic science would face its toughest challenge yet.

0:34:12 > 0:34:16On February the 26th, 1949,

0:34:16 > 0:34:19John Haigh was being questioned by police

0:34:19 > 0:34:25about the disappearance of a woman - 69-year-old Olive Durand-Deacon.

0:34:26 > 0:34:31Haigh was more than willing to help the police with their enquiries.

0:34:31 > 0:34:35What he told them was totally unexpected.

0:34:36 > 0:34:40"Mrs Durand-Deacon no longer exists.

0:34:40 > 0:34:46"She has disappeared completely and no trace can ever be found.

0:34:46 > 0:34:49"I have destroyed her with acid.

0:34:49 > 0:34:52"Every trace has gone.

0:34:52 > 0:34:56"How can YOU prove a murder if there is no body?"

0:35:02 > 0:35:05Haigh went on to gleefully detail

0:35:05 > 0:35:08how he'd killed Mrs Olive Durand-Deacon.

0:35:08 > 0:35:12He lured her to his workshop, shot her in the back of the head

0:35:12 > 0:35:17and then dumped her body in a barrel of sulphuric acid.

0:35:17 > 0:35:21Three days later, when the acid had dissolved her body,

0:35:21 > 0:35:26he returned and simply poured the sludge onto the ground outside.

0:35:26 > 0:35:29But his sinister boasting didn't stop there.

0:35:33 > 0:35:36He admitted five further murders.

0:35:39 > 0:35:40After each killing,

0:35:40 > 0:35:44he assumed control of his victim's financial affairs.

0:35:45 > 0:35:49Haigh was a serial killer who murdered for money.

0:35:55 > 0:35:56Despite his confession,

0:35:56 > 0:36:01Haigh was convinced that he'd get away with all six murders.

0:36:01 > 0:36:04He fancied himself as a bit of a legal expert and he knew

0:36:04 > 0:36:09that the police would need more than just a confession to convict him.

0:36:09 > 0:36:13This is because of an aspect of law known as Corpus Delicti,

0:36:13 > 0:36:16literally meaning "body of the crime".

0:36:16 > 0:36:19Now, Haigh thought that a physical corpse would be needed

0:36:19 > 0:36:22to prove that a murder had taken place

0:36:22 > 0:36:26and that's why he dissolved his victims' bodies in acid.

0:36:29 > 0:36:31Haigh had it wrong.

0:36:33 > 0:36:38In law, Corpus Delicti doesn't refer to the physical body of the victim.

0:36:40 > 0:36:42It means the body of evidence

0:36:42 > 0:36:45that collectively proves a crime has taken place.

0:36:47 > 0:36:52Haigh wasn't as immune to prosecution as he thought.

0:36:54 > 0:36:58So, somewhat bizarrely, the police were tasked with the job

0:36:58 > 0:37:03of finding corroborating evidence to support Haigh's confession.

0:37:03 > 0:37:07But how do you do that with nothing more than a pile of sludge?

0:37:11 > 0:37:15Police called in eminent pathologist Keith Simpson.

0:37:15 > 0:37:21To him, Haigh's arrogance was like a red rag to a bull.

0:37:22 > 0:37:25He set out to prove that the sludge

0:37:25 > 0:37:28was indeed the remains of Olive Durand-Deacon.

0:37:33 > 0:37:38At the murder scene, Simpson was lead to the patch of greasy sludge

0:37:38 > 0:37:43that Haigh claimed were the remains of Olive Durand-Deacon.

0:37:43 > 0:37:45At first, it didn't look very promising.

0:37:45 > 0:37:48But then, he had an idea.

0:37:48 > 0:37:53Focusing his mind on the victim, he wondered - what, if anything,

0:37:53 > 0:37:57would survive of a body after three days in an acid bath?

0:37:57 > 0:38:03And then, meticulously, he began to search every inch of the ground.

0:38:04 > 0:38:07Finally, he found something -

0:38:07 > 0:38:09a bright red stone.

0:38:09 > 0:38:14Now, to the police, this just looked like another piece of gravel,

0:38:14 > 0:38:17but Simpson knew this was a key piece of evidence

0:38:17 > 0:38:19that would help him convict Haigh.

0:38:23 > 0:38:25What Simpson was looking for

0:38:25 > 0:38:29was some part of Mrs Durand-Deacon's body

0:38:29 > 0:38:32that would resist the corrosive effects of the acid.

0:38:34 > 0:38:37To demonstrate Simpson's thinking,

0:38:37 > 0:38:40what I've got here is two beakers of acid

0:38:40 > 0:38:44and, into them, I'm going to put a couple of soluble aspirin.

0:38:44 > 0:38:46One in there...

0:38:46 > 0:38:48and one in here.

0:38:48 > 0:38:52Now what you can immediately see is that,

0:38:52 > 0:38:56while this one's fizzing away, because the acid is dissolving it,

0:38:56 > 0:39:00absolutely nothing is happening inside this one, and that's because

0:39:00 > 0:39:05I've coated it with a layer of fat, in this case lard.

0:39:05 > 0:39:07Now, when I was at medical school,

0:39:07 > 0:39:12we were taught that a fat, fertile, fair, female of 40

0:39:12 > 0:39:16was the perfect candidate to get something called gallstones.

0:39:16 > 0:39:20Simpson knew that Olive was overweight, elderly and sedentary,

0:39:20 > 0:39:22and he thought she too

0:39:22 > 0:39:25would be just the kind of person who might get them.

0:39:28 > 0:39:32Just like fat, gallstones are resistant to the effects of acid.

0:39:34 > 0:39:38The small, facetted red stone that he had found

0:39:38 > 0:39:44wasn't just a piece of gravel, it was a human gallstone

0:39:44 > 0:39:48and it was the first piece of evidence that really proved

0:39:48 > 0:39:51that what had appeared like just a pile of sludge

0:39:51 > 0:39:54was in fact a human body.

0:39:58 > 0:40:00Convinced these were human remains,

0:40:00 > 0:40:03Simpson had the mixture of sludge and dirt -

0:40:03 > 0:40:10in total nearly 100kg - sent back to the laboratory to be analysed.

0:40:12 > 0:40:14Sifting through the sludge like this,

0:40:14 > 0:40:19they were able to find 18 fragments of human bone.

0:40:20 > 0:40:24X-ray analysis showed that the fragments were fragile

0:40:24 > 0:40:29even before they went in the acid, with signs of osteoarthritis.

0:40:29 > 0:40:32This is a condition that's suffered by elderly people

0:40:32 > 0:40:36and he knew that Olive had been 69 at the time of her disappearance.

0:40:40 > 0:40:44Simpson had established the presence of human remains

0:40:44 > 0:40:47and the likely age of the victim,

0:40:47 > 0:40:51but could he now prove that the person in the sludge was female?

0:40:53 > 0:40:55Of all the bones in the human body,

0:40:55 > 0:41:00none shows the variation between the sexes more clearly than the pelvis.

0:41:00 > 0:41:04I've got a female pelvis here and also a male one.

0:41:04 > 0:41:07The female pelvis is broad,

0:41:07 > 0:41:09to assist in childbirth,

0:41:09 > 0:41:12whereas the male pelvis has got a much more

0:41:12 > 0:41:15acute angle at the pubic arch and, because the man doesn't need

0:41:15 > 0:41:18to have babies, it's narrow at the pelvic outlet.

0:41:18 > 0:41:21Now it's pretty obvious, when you look at the differences

0:41:21 > 0:41:23on this big a scale, what they are.

0:41:24 > 0:41:29But all that Simpson had to go by was a tiny fragment of bone.

0:41:29 > 0:41:32Fortunately, what he found in that fragment

0:41:32 > 0:41:36was a section of a groove called the preauricular sulcus.

0:41:36 > 0:41:39This is more marked in women than men

0:41:39 > 0:41:44and, from this, Simpson was able to tell that the victim was female.

0:41:46 > 0:41:49But there was a further clue to be found.

0:41:52 > 0:41:56Over two stone of human fat were extracted from the sludge.

0:41:59 > 0:42:01The victim was obviously portly...

0:42:04 > 0:42:08..just like Olive Durand-Deacon.

0:42:08 > 0:42:11From within the sludge, Simpson and his team

0:42:11 > 0:42:16had managed to resurrect the figure of an overweight elderly lady,

0:42:16 > 0:42:20who suffered from gallstones and arthritis,

0:42:20 > 0:42:23and she had been dissolved in sulphuric acid.

0:42:28 > 0:42:31Under Simpson's forensic gaze,

0:42:31 > 0:42:35the sludge was revealed as a match for the missing woman.

0:42:35 > 0:42:38It was enough to corroborate Haigh's confession.

0:42:47 > 0:42:50John Haigh was hanged here, at Wandsworth Prison,

0:42:50 > 0:42:53on the 6th of August, 1949.

0:42:53 > 0:42:56The case of the Acid Bath Murderer

0:42:56 > 0:43:01became a powerful advertisement for the skills of forensic scientists.

0:43:03 > 0:43:05There could no longer be any doubt.

0:43:05 > 0:43:08To prove a murder, you didn't need a body.

0:43:13 > 0:43:16In the century between the killing of George Parkman

0:43:16 > 0:43:18and the Acid Bath Murderer,

0:43:18 > 0:43:23forensic science had developed into a formidable force for justice.

0:43:25 > 0:43:29Murder victims now rarely stayed anonymous for long,

0:43:29 > 0:43:31but identifying a killer

0:43:31 > 0:43:34directly from evidence left at a crime scene

0:43:34 > 0:43:38was still only possible from fingerprints.

0:43:39 > 0:43:41What would change this was perhaps

0:43:41 > 0:43:47the most crucial breakthrough in the history of forensic science.

0:43:47 > 0:43:51It came nearly four decades after the execution of John Haigh,

0:43:51 > 0:43:55on the back of a particularly harrowing case.

0:43:58 > 0:44:01On the 31st of July, 1986,

0:44:01 > 0:44:05the body of a schoolgirl, Dawn Ashworth,

0:44:05 > 0:44:09was discovered here in a secluded area of Enderby,

0:44:09 > 0:44:12a village just outside Leicester.

0:44:12 > 0:44:15She'd been raped and strangled.

0:44:15 > 0:44:19Almost immediately, the police named their prime suspect -

0:44:19 > 0:44:23a 17-year-old boy called Richard Buckland, who'd been spotted

0:44:23 > 0:44:26acting suspiciously near where Dawn's body was found

0:44:26 > 0:44:29and who appeared to know details of the crime

0:44:29 > 0:44:31that weren't public knowledge.

0:44:33 > 0:44:36As soon as the police got him in for questioning,

0:44:36 > 0:44:39he confessed to the murder,

0:44:39 > 0:44:43but his confession raised a difficult question for the police.

0:44:46 > 0:44:50Was he responsible for, not one murder, but two?

0:44:52 > 0:44:56Three years earlier, the body of 15-year-old Lynda Mann

0:44:56 > 0:44:59had been found in the nearby village of Narborough.

0:45:01 > 0:45:03She'd also been raped and strangled.

0:45:07 > 0:45:09Police were absolutely convinced

0:45:09 > 0:45:12the same man was responsible for both murders...

0:45:13 > 0:45:18..but Richard Buckland refused to confess to the earlier murder.

0:45:23 > 0:45:25The police didn't have enough evidence

0:45:25 > 0:45:29to directly connect Buckland to the murder of Lynda Mann,

0:45:29 > 0:45:31but they did have something else -

0:45:31 > 0:45:38semen samples taken from both crime scenes - and this gave them an idea.

0:45:38 > 0:45:40They'd heard about a brand-new method

0:45:40 > 0:45:44for establishing paternity with DNA being pioneered

0:45:44 > 0:45:49by Dr Alec Jeffreys and his team at the University of Leicester.

0:45:49 > 0:45:53Desperate for a break, they decided to call Dr Jeffreys

0:45:53 > 0:45:56and ask him the million dollar question -

0:45:56 > 0:46:01could his technology be used, not for establishing a father,

0:46:01 > 0:46:03but for catching a killer?

0:46:07 > 0:46:11'It was a question no-one had asked him before,

0:46:11 > 0:46:12'but he was far from confident

0:46:12 > 0:46:17'that his new DNA techniques would work within a police investigation.'

0:46:19 > 0:46:22Well, it was out of the blue and actually quite terrifying

0:46:22 > 0:46:25because we knew, in principle, we had a technology that might be

0:46:25 > 0:46:27applicable to forensics, but nobody had ever done it.

0:46:27 > 0:46:29- Mm-hm.- It had never been applied in anger

0:46:29 > 0:46:31in a real live murder investigation,

0:46:31 > 0:46:34so I accepted to take on the case

0:46:34 > 0:46:37in the full expectation of getting absolutely nothing out of it.

0:46:37 > 0:46:39This was going to be a big shot in the dark.

0:46:42 > 0:46:44Jeffreys and his team

0:46:44 > 0:46:48were given samples taken from both crime scenes.

0:46:48 > 0:46:52They analysed them using a new technique they'd developed

0:46:52 > 0:46:55called DNA profiling.

0:46:55 > 0:47:00This technology represented an individual's genetic code

0:47:00 > 0:47:03as a two-band pattern.

0:47:03 > 0:47:07It may look simple, but the chances of two unrelated people

0:47:07 > 0:47:12having the same profile are millions to one.

0:47:12 > 0:47:17The entire case would rest on this ground-breaking work.

0:47:19 > 0:47:23These are the original set of DNA profiles from this case,

0:47:23 > 0:47:28so, if we look through here, this is the first victim

0:47:28 > 0:47:32- and what you see here is a two-band DNA profile.- So this is Lynda Mann,

0:47:32 > 0:47:35- who was the first girl that was murdered?- That's correct, yes, yeah.

0:47:36 > 0:47:39'This second track was made with a sample

0:47:39 > 0:47:43'taken from Lynda's body after she'd been raped.

0:47:43 > 0:47:48'Again, her own DNA profile is clearly visible,

0:47:48 > 0:47:52'but this time, it's not the only one.'

0:47:53 > 0:47:56But you also see another two bands up here,

0:47:56 > 0:48:00which must be the DNA profile of the semen from the assailant.

0:48:02 > 0:48:05We now move to the second victim.

0:48:05 > 0:48:09- So Dawn Ashworth?- Dawn Ashworth. - Yeah.- So, you see her DNA profile -

0:48:09 > 0:48:12- completely different from this profile...- Yes.- ..and that profile.

0:48:13 > 0:48:16'This profile here was obtained

0:48:16 > 0:48:20'from small amounts of semen recovered alongside Dawn's body.'

0:48:22 > 0:48:26If one looks very carefully, there's trace amounts of semen in there.

0:48:26 > 0:48:30You can see a two-band DNA profile there, that doesn't match the victim,

0:48:30 > 0:48:33so it must be from the perpetrator and, much more importantly,

0:48:33 > 0:48:37that profile seems to match the profile of the first victim.

0:48:38 > 0:48:40The police were right -

0:48:40 > 0:48:43the same man had committed both murders -

0:48:43 > 0:48:45but there was a problem.

0:48:45 > 0:48:50The DNA profile of their prime suspect, Richard Buckland,

0:48:50 > 0:48:53didn't match the unknown assailant.

0:48:53 > 0:48:58He couldn't be the killer of Dawn Ashworth and Lynda Mann.

0:48:58 > 0:49:00This is a really important point,

0:49:00 > 0:49:04that the first time DNA was ever used in anger in a criminal investigation

0:49:04 > 0:49:07was not to establish guilt, it was to establish innocence.

0:49:07 > 0:49:10And I think, given this young man's confession

0:49:10 > 0:49:13and some circumstantial evidence surrounding the case,

0:49:13 > 0:49:15my guess, he would've been found guilty

0:49:15 > 0:49:18and jailed for the rest of his life for those offences,

0:49:18 > 0:49:21and the true perpetrator would've been left free to carry on offending.

0:49:25 > 0:49:29Richard Buckland became the first person in history

0:49:29 > 0:49:32to be exonerated on the basis of DNA...

0:49:34 > 0:49:37..but that meant the killer was still out there.

0:49:39 > 0:49:43Police realised that, if DNA could be used to prove innocence,

0:49:43 > 0:49:47it could also be used to establish guilt,

0:49:47 > 0:49:52and they embarked on the world's first-ever DNA manhunt.

0:49:53 > 0:49:58The police were convinced that the murderer was a local man.

0:49:58 > 0:50:03Over 5,000 men in the area had blood and saliva samples taken

0:50:03 > 0:50:07and a DNA profile was established for each and every one of them.

0:50:09 > 0:50:12The whole process took more than six months

0:50:12 > 0:50:15and was known by the press as The Blooding.

0:50:17 > 0:50:20But not a single profile matched the samples

0:50:20 > 0:50:24recovered from Dawn Ashworth and Lynda Mann.

0:50:24 > 0:50:28It looked as if the murderer had got away scot-free.

0:50:28 > 0:50:32MUSIC: True Faith by New Order

0:50:33 > 0:50:37Now the police were in desperate need of a break.

0:50:46 > 0:50:49In August 1987, a group of bakery workers

0:50:49 > 0:50:52were enjoying a lunchtime drink when one of them,

0:50:52 > 0:50:57Ian Kelly, started to tell an interesting story about the case.

0:50:57 > 0:51:01He described how he'd been approached by another one of

0:51:01 > 0:51:05their colleagues, Colin Pitchfork, with a very strange proposition.

0:51:07 > 0:51:10Pitchfork said that he'd already given a blood sample

0:51:10 > 0:51:12to the police to cover for a friend of his

0:51:12 > 0:51:16who was a bit worried he might be framed for the murders,

0:51:16 > 0:51:19and now he, Pitchfork, was concerned that he

0:51:19 > 0:51:23was going to get into trouble for this small act of kindness.

0:51:23 > 0:51:27On the basis of his plea, and for a small amount of £200,

0:51:27 > 0:51:31Ian Kelly had agreed to take the DNA test for him.

0:51:33 > 0:51:37Listening to this story was a female bakery worker,

0:51:37 > 0:51:39who was very concerned by what she heard,

0:51:39 > 0:51:42and her concerns preyed on her mind for weeks

0:51:42 > 0:51:45until eventually she took them to the police.

0:51:46 > 0:51:49This was the breakthrough they'd been looking for.

0:51:53 > 0:51:56Colin Pitchfork, a local 27-year-old baker,

0:51:56 > 0:51:58was swiftly arrested.

0:51:58 > 0:52:02A sample of his DNA was sent for analysis.

0:52:04 > 0:52:07Having got the wrong man first-time round, obviously there was

0:52:07 > 0:52:10a slight concern they'd got the wrong person second-time round,

0:52:10 > 0:52:13so it was a big relief when the phone call came through and said,

0:52:13 > 0:52:15"Yes, we've got a full DNA match...

0:52:15 > 0:52:17"with semen from both of these victims.

0:52:17 > 0:52:19"This is definitely your man."

0:52:23 > 0:52:26On the 22nd of January, 1988,

0:52:26 > 0:52:30Colin Pitchfork was convicted of the murders of Dawn Ashworth

0:52:30 > 0:52:33and Lynda Mann,

0:52:33 > 0:52:35and sentenced to life imprisonment.

0:52:37 > 0:52:41He became the first person ever to be convicted of murder

0:52:41 > 0:52:44on the basis of genetic evidence.

0:52:58 > 0:53:01Nearly 30 years after this pivotal case,

0:53:01 > 0:53:07we're now on the verge of another revolution in forensic DNA analysis.

0:53:08 > 0:53:13Scientists are attempting something that was once thought impossible -

0:53:13 > 0:53:16to recreate a face from DNA.

0:53:20 > 0:53:24It's called Molecular Photofitting and though it

0:53:24 > 0:53:29sounds like science fiction, it could soon be a forensic reality.

0:53:29 > 0:53:32I'm on my way to Belgium to meet a team of researchers

0:53:32 > 0:53:34who believe they could make it happen.

0:53:38 > 0:53:40If they succeed,

0:53:40 > 0:53:44the face of a killer could be obtained directly from DNA

0:53:44 > 0:53:46left at a crime scene and, today,

0:53:46 > 0:53:49I'm playing the part of the criminal.

0:53:51 > 0:53:54Eight weeks ago, DNA was extracted from my saliva

0:53:54 > 0:53:59and the results sent anonymously to a group of scientists.

0:54:00 > 0:54:05They're now using that data to build a picture of my face

0:54:05 > 0:54:08as predicted by my genes.

0:54:08 > 0:54:11The question is - will it look anything like me?

0:54:15 > 0:54:17I'm curious to arrive in Belgium now.

0:54:17 > 0:54:20It could be because I was just rubbish at genetics

0:54:20 > 0:54:24at medical school and never really understood how it all worked.

0:54:24 > 0:54:27I just fail to understand how someone could take

0:54:27 > 0:54:31a sample of my saliva and turn that into a picture of me.

0:54:40 > 0:54:42I'm meeting Dr Peter Claes,

0:54:42 > 0:54:46a medical-imaging specialist at the University of Leuven.

0:54:47 > 0:54:49Along with colleagues in the USA,

0:54:49 > 0:54:54he has built up a database of faces and DNA.

0:54:54 > 0:54:58Armed with this, he's able to model how a face is constructed

0:54:58 > 0:55:01based on just 20 genes.

0:55:04 > 0:55:07I know that, eight weeks ago, he was sent a sample of my DNA

0:55:07 > 0:55:11from my saliva and now the moment has arrived

0:55:11 > 0:55:13when I'm going to go into this room

0:55:13 > 0:55:18and see if the face, the model of the face that he's come up with

0:55:18 > 0:55:23purely on the base of my spit, looks anything like me.

0:55:32 > 0:55:34Gosh, is that really me?

0:55:35 > 0:55:40I can see the eyes are my eye colour and...does it look like me, Peter?

0:55:40 > 0:55:43I think it does in several aspects.

0:55:43 > 0:55:46I can tell you that your eyebrows are indeed sticking more...

0:55:46 > 0:55:49forward more and your chin as well,

0:55:49 > 0:55:52so you have a very prominent, specific chin compared to

0:55:52 > 0:55:54an average European female,

0:55:54 > 0:55:57which is, in my eyes, not a bad result.

0:55:57 > 0:56:02You have very flat cheeks but, of course, that's a tricky area

0:56:02 > 0:56:05to actually predict accurately because it's heavily influenced

0:56:05 > 0:56:08by your diet, which is an environmental factor.

0:56:08 > 0:56:10The nose could have been better.

0:56:10 > 0:56:13And, in fact, I broke my nose when I was younger,

0:56:13 > 0:56:16so that might explain why the nose doesn't exactly match.

0:56:16 > 0:56:19Exactly, it's an environmental effect on your face,

0:56:19 > 0:56:22which is clearly not coded in your DNA

0:56:22 > 0:56:25and hence it was not revealed by the prediction.

0:56:25 > 0:56:30If we superimpose this predicted face over a photo,

0:56:30 > 0:56:34the accuracy of the technique is revealed

0:56:34 > 0:56:39and seeing this likeness of me is truly uncanny.

0:56:40 > 0:56:45The eyes, nose, mouth and chin are all roughly in the right place,

0:56:45 > 0:56:48but the features are more rounded than in reality.

0:56:49 > 0:56:52Police couldn't publish a Molecular Photofit like this

0:56:52 > 0:56:54and hope to catch a killer...

0:56:55 > 0:56:58..but that's not how Peter sees the technique being used

0:56:58 > 0:57:00in a criminal investigation.

0:57:02 > 0:57:05If I would bring this result to an investigator,

0:57:05 > 0:57:09I wouldn't necessarily give him the image to be broadcast,

0:57:09 > 0:57:11I would talk to him and say, "OK, what you're looking for is

0:57:11 > 0:57:17"indeed a European female, but with particular eyebrows and chin."

0:57:17 > 0:57:21That information is already of high value because it can focus

0:57:21 > 0:57:24the investigation on looking for such a person.

0:57:27 > 0:57:29This may be new science,

0:57:29 > 0:57:33but Peter and his colleagues are rapidly developing the technology.

0:57:34 > 0:57:40The number of genes used is being expanded from 20...

0:57:40 > 0:57:41to 200.

0:57:42 > 0:57:46Molecular Photofitting is only going to become

0:57:46 > 0:57:48more accurate in the coming years.

0:57:50 > 0:57:56And, as we've seen from history, all it will take is one case,

0:57:56 > 0:57:58one key breakthrough,

0:57:58 > 0:58:01to establish it on the forensic stage.

0:58:07 > 0:58:10Next time, crime scenes.

0:58:10 > 0:58:13I'll discover how mud can catch a killer,

0:58:13 > 0:58:17I'll try to make sense of blood-spatter patterns

0:58:17 > 0:58:22and I'll scrutinise the single thumb print that hanged two men.

0:58:22 > 0:58:25Delve deeper with the Open University

0:58:25 > 0:58:29and find out more about the science behind forensics.

0:58:29 > 0:58:30Go to...

0:58:34 > 0:58:37..and follow the links to the Open University.