The quick take home here is that any photograph with a high enough resolution will provide sufficient data to then compare with the person in question and support a positive identification. We are already doing this with faces commercially and forensics have used finger prints forever.
The point is that there will normally be enough data. Not enough to locate an unknown but enough to confirm a suspect and often as not to do much better.
I personally would like to see prints collected upon birth along with DNA. This would be expensive but costs have been dropping. This would go a long way toward making much violent crime impossible to execute without identification. Recall how no one attempts phone harassment today..
Sue Black Catches Paedophiles by Looking at the Marks on Their Hands
When a paedophile or rapist films their crime, professor Sue Black can track them down using nothing more than the veins, scars and other markings on their hands.
One day in 2006, Sue Black, a professor at the University of Dundee's department of Anatomy and Forensic Anthropology,
received a phone call from a man called Nick Marsh. He was a forensic
photographer who had worked with Black 17 years earlier as part of a
team sent by the Foreign Office to examine the bodies of victims of war
crimes in Kosovo. Marsh knew that Black had a talent for identifying
people from scraps of flesh and bone. Now he had evidence of a different
kind and wondered if she could help.
The piece of evidence was an eight-second-long digital
video clip. Marsh had been working on a case involving a teenage girl
who had alleged that her father had been coming into her bedroom at
night to molest her. When her mother refused to believe her, the girl
left her webcam running all night, pointed at her bed. The camera
captured a person's hand and forearm touching her. Her father denied
that he was the person in the video. "It was one of the spookiest and
scariest things that I have ever seen," explains Black. "A real sort of
horror movie."
Marsh asked Black if there was a way to identify
the perpetrator. She didn't have clue. "I'd never done anything like
that before. I'd never identified anyone using a hand," she says. But
after studying the footage, Black noticed something that had escaped her
before: the veins on the back of the man's hand were visible. In the
dark, the camera had reverted to infrared mode, and in those conditions
the deoxygenated blood in veins shows up as black lines. Black, an
expert in anatomy, knew that hand-vein patterns are unique from person
to person, even in identical twins. She asked the police to take
photographs of the father's hand and forearm. The vein patterns matched.
Black appeared in court as an expert witness for
the prosecution, presenting her vein-pattern analysis. It was the first
time in British legal history that evidence of this kind was presented
in court proceedings. When she was introduced, the judge had to stop the
trial for 90 minutes to ask her to explain the principles behind her
analysis. Black explained her rationale, but conceded that she didn't
have statistics showing the likelihood of the hands matching. "That
research had never been done. I could say no more than everything
matched, and we couldn't say it definitely wasn't him," she says.
Still, it was strong evidence and the prosecuting barrister expected the father to be found guilty. However, he was acquitted.
"I
asked the barrister if there was something we had done wrong or
something in the science that I had not been able to convey," Black
recalls. "She said, 'No, there was no problem with the science. The jury
had just not believed the girl. They thought she didn't seem upset
enough.'"Black was dumbfounded.
Shortly after the
trial of the girl's father, the Serious Organised Crime Agency (SOCA)
asked Black if she could help with an ongoing police investigation
called Operation Ore.
It was a long-running investigation of more than 7,000 British people
suspected of downloading indecent images, after the FBI had found their
details on the database of a child-porn distributor in Texas.
The
operation became the UK's largest-ever computer crime investigation,
involving the arrest of more than 3,700 people, including several public
figures such as The Who guitarist Pete Townshend and The Thick of It actor and writer Chris Langham.
Black was again asked if she could identify
people in the images. "Operation Ore was the first time I realised these
kind of cases could have such a volume," she says. "I was naive. I
thought it was all about isolated people in isolated cases." According
to Black, about a million images of child abuse are uploaded to the dark
web every day. When police seize mobile phones and find indecent
images, they discover, on average, about 100,000 individual images. "It
is a huge problem, and the police can't get near looking at them all,
nor arresting their way out of it," Black says.
In
the end, she worked only briefly as a consultant on Operation Ore, which
soon became mired in controversy when journalists revealed flaws in
police methods.
Nevertheless, it was a turning point
for Black. During Operation Ore, she became fully aware of a problem
that she didn't realise existed and that she might be the person who
could do something about it.
But in the months after
the trial, it occurred to her that she might have stumbled across a new
idea. Marsh had mentioned that the police were seeing an ever-increasing
number of indecent images and videos of children. Abusers often
appeared themselves: "Sexual abuse of children is often about power, and
the touching is a part of that," says Black. "When a perpetrator views
an image of themselves abusing a child, they are reliving the enactment.
If there's a part of them present in the image, it gives them an extra
feeling of involvement."
The problem was that, in
most cases, the only visible parts of the abusers' bodies were their
hands and genitalia. Previously it had been widely assumed that such
evidence was not enough to incriminate someone. But Black was
unconvinced. "There was a research route that had never been fully
explored," she says. "I had been involved in crimes where the victim was
dead but these cases had live victims and perpetrators. I thought there
might be something we could extract from those images and use in a
meaningful way. I thought, 'We should be researching it.'"
Sitting in her 70s office with its high windows to let in light, Black looks very much the academic in a cardigan, with her hair plaited. Her manner is no-nonsense but affable.
Black
grew up the youngest of two daughters in a blue-collar Inverness
household, and was the first of her family to attend university - she
studied biology then human anatomy at Aberdeen. She began her career
teaching at St Thomas' Hospital in London. Stints of body-identification
work for the police, then the Foreign Office, led to her working in
Kosovo, for which she was awarded an OBE in 2001. She has since worked
in conflict zones in countries such as Iraq, and in Thailand after the
2004 tsunami.
In 2003, Black took over the University
of Dundee's Centre for Anatomy and Human Identification and began
developing the links between anatomy and forensic science. In 2016, in
recognition of her services to forensic anthropology, she was made a
Dame.
The teams that work on forensic cases are,
Black says, "very close knit. At the end [of a case] we will sit and
talk it through. Counselling is always available, though we haven't
needed it yet. We are very tuned in to each other, and if someone is
uncomfortable we deal with it there and then. When a team is exposed to
this sort of thing, which is as bad as it gets, each of you has to know
that each member is not suffering themselves."
After Operation Ore, Black realised that hand
analysis would be taken seriously only if it had a genuinely scientific
foundation, rather than being based on ad hoc comparisons. It was fine
to show the vein patterns of an abuser and the accused matched, but if
the accused contended that many people had matching veins, Black
wouldn't be able to back up her argument with any scientifically
validated evidence. In other words, she would need a substantial
database of hundreds of people, compiled with a minuscule budget.
In April 2007, Black's department won a contract to
teach more than 550 police officers, coroners and legal officials about
disaster-victim identification. Black asked attendees to have photos
taken of their hands, forearms, feet and legs. Most agreed.
More recently, she helped a mother's fight to prove what had happened to her son's body. She carried out an exhumation at his burial plot in Edinburgh, and confirmed that no humans reminds were inside the coffin.
By
2008, she'd published a study confirming the validity of vein-pattern
analysis. Shortly after, she was asked to help in another case. The
defendants were eight men belonging to Scotland's largest-known
paedophile network. For years, they'd colluded to rape and sexually
abuse children, and shared at least 125,000 images of the abuse. The
details were so harrowing that during the hearing, the public and media
were barred from seeing the images, and counsellors were made available.
At one point, the jury heard that one of the accused had circulated a
request for "porn with young Down's syndrome or learning-difficulty
kids".
Many images featured men abusing the children of
friends. A key photo - later known as "the Hogmanay image" - showed one
of the two ringleaders, Neil Strachan, 41, attempting to rape an
18-month-old boy whom he was babysitting on New Year's Eve in 2005. The
only parts of Strachan's body visible were his penis and left hand. It
was this image that Black analysed.
She was aided by a
mistake on Strachan's part. His defence team ordered that photographs
be taken of his thighs, their intention presumably to show that body
parts could not be used to identify someone. However, when the
photographer was taking the picture, he asked his subject to hold the
photographic scale, which, says Black, "gave us a beautiful view of the
accused's thumbs".
Black compared the left thumb in
the picture with the Hogmanay image and found matching details,
including an unusually shaped lunule, the white area at the base of the
nail. "This time, I was able to go back to my database and put
statistics to the data." In October 2009, Strachan was sentenced to life
imprisonment with a minimum term of 16 years, cut on appeal to nine
years.
Hands can be used to verify a person's identity in
two ways. First, they pick up marks and injuries - more than 20 per
cent of people attending A&E in the UK have hand injuries. Second,
it has in-built morphological features which are unique to the
individual - fingertip whorls, palm prints and vein patterns. When a
body is growing inside the womb, cells assemble spontaneously, rather
than following a pre-established blueprint. This means vein patterns are
one-offs. Veins also have the advantage of being enclosed by skin and,
unlike fingerprints, can't be altered.
Black analyses mainly the backs, or the dorsum,
of hands, as these tend to be predominantly visible in the footage she
works with in criminal cases. She first maps a grid of 24 cells on to
the hand, covering everything from fingernails to wrist. Then she
analyses each cell, looking for identifying marks and studying vein
patterns, drawing dark lines over them on-screen to make them more
visible.
The features she most commonly checks are veins, scars,
freckles, birthmarks, moles, nails and skin creases on knuckles. Each
one is scrutinised. For example, scars will be classified according to
whether they are linear or non-linear, or surgical or accidental, and
then by the direction in which they run. When she compares the accused's
hand with the database, she can use geometrical formulae to work out
the chances of anyone else having the same markings and vein patterns.
Black's
database - she has now analysed 1,000 hands - throws up fascinating
insights. For instance, you are most likely to get a linear scar on the
tip of your second finger, or the middle of the back of your hand. No
one seems to get moles on their little fingers, and if you have moles in
the same places on both hands, it will be somewhere in the lower half
of a triangle drawn between the knobs of your wrists and second knuckle.
On average, men have 50 per cent more scars than
women, but right-handed men are more likely to scar their left hands,
while right-handed women tend to scar their right - no one knows why.
Black is fascinated by the stories that the hands in her database tell.
One of her papers quotes lines from Arthur Conan Doyle's A Study in Scarlet:
"By a man's finger-nails, by his coat-sleeve, by his boots, by his
trouser-knees," declares Sherlock Holmes, "by the callosities of his
forefinger and thumb, by his expression, by his shirt-cuff - by each of
these things a man's calling is plainly revealed."
Sometimes
a case challenges Black's methodology. In 2014, the Greater Manchester
Police asked her to work on the case of paedophile Jeremy Oketch, a
30-year-old pharmacist who had twice raped a two-year-old girl and
filmed the assaults. Although it was impossible to prove, the child's
silent compliance suggested that she had been drugged. And although the
police had 55 minutes of footage to examine, the only visible parts of
the rapist were a hand and his penis.
The video was
so distressing, recalls Black, that when judge Hilary Manley left the
courtroom to view it, she returned visibly shaken. Was Black affected
herself? "Images of child abuse affect everyone who views them," she
says. "I feel anxious watching video because you don't know what's
coming next. But you have to stay objective. It's not my place to go
back to analyse the incident, it's my job to find something of value to
the investigation."
The Oketch case presented her with two technical
problems. First, he was black, "and all the people we had looked at
previously had been white. I didn't know if all the features would be as
visible on black skin, but they were." Second, a lot of the footage was
clear, the matches were numerous and potential divergences almost
totally absent. That sounds ideal, but such apparent certainty brings
its own risks. Black takes a file from a cabinet and slips out her
report on Oketch to show me (it is in the public domain, having been
used in a Crown prosecution). Information is tabulated. Under "Hand"
appears a long list of features: "Hand morphology", "Thumb nail groove
from asymmetrical lunule", "Vein pattern" and so on. Under "Penis", a
similar list: "Penile morphology", "Vein pattern", "Lateral deviation".
Each feature is marked to show whether it's the same on the rapist and
the suspect. They all are. "And as I learned, that can be a challenge,
because it makes you ask yourself if you're really seeing everything.
Part of this work is knowing how to look; asking yourself what you might
not be noticing," Black says.
In the end, the match
appeared strong. When presented with Black's report, Oketch changed his
plea from not guilty to guilty; he got 15 years. That plea change was
important, Black says. It meant money that would otherwise have been
spent on trials was saved. It also meant the child was spared from
having to give evidence in court.
Black's team helps police forces around the world -
including the FBI, Interpol and Europol - and works on 30 to 50 cases a
year. In the cases Black has worked on since 2006, the percentage in
which the accused have changed their plea to guilty in response to her
analysis stands at 82. Black also takes on cases related to
circumstances such as those in which the perpetrator has disguised their
face. Grants have helped expand the database and her team have reduced
the time it takes to compile a report.
When a case comes in from the police, Black
administrates the project, but the client pays the university; any
payment to Black's team could be seen to compromise its objectivity.
Images or video material are delivered on encrypted drives and handed to
her in person. Black works in a team of three but she first views all
video evidence herself, absorbing the initial shock on behalf of
colleagues. "You have to view it all the first time to know what's
coming," she explains. "Then you can narrow it down and look at parts
that are more important for the job you have to do."
After
that, she shares material she thinks is important with Lucina Hackman, a
senior lecturer in human identification at the department, and both
women independently single out the pictures that best highlight key
anatomical features. Then they agree about the offender's important
features and a photographic specialist on the team, Chris Rynn, will
enhance the images digitally. Once they have established the offender's
features, they study images of the suspect, trying to establish a match.
Roughly
speaking, the degree of certainty on any biometric is dictated by the
size of a data set. Black's is not yet big enough to justify stating a
statistical probability, so instead she follows the system used by the
judiciary, which objectively grades the possibility of a match.
Even
with clear images of a suspect's and perpetrator's hands, it is
impossible to scientifically guarantee a match, as that depends on all
the anatomical features present. A suspect can be excluded with 100 per
cent certainty, but a match can only carry a grade of "strong support"
that the suspect and the offender are the same person. This equates to
between a 1-in-1,000 to 1-in-10,000 chance that it could be someone
else.
Often this is enough for the accused to change
their plea as there is normally additional evidence to implicate the
person. If you're wondering why no one is investing billions to create
million-strong data sets, Black says it's because there's no money for
research into catching child abusers. In the forensic field, most
research funding goes into DNA, because it's what they know and trust
and there's a drive to do things quicker and cheaper.
"We've looked at vein patterns on the right and
left hands of all individuals on the database and we haven't been able
to find any two that match," Black says. "We have expanded the database
many times since we began, but we need much bigger databases to
establish greater degrees of certainty. We think we might get to
something that's as good as fingerprinting." Black is attempting to
automate the process of searching for repeated patterns, creating
algorithms that are able to extract the features from millions of stills
or video images. "We've done the pilot project, which shows that we can
extract vein patterns and pigment patterns. We're now looking at
whether we can do skin-crease patterns on knuckles," Black says. "When
you layer all these features and patterns, you increase the probability
of identifying the right individual to the fingerprint level, or even
perhaps the DNA level of certainty. It could allow us to identify and
look for the first-generation producers. It would also mean reducing the
strain that these images places on officers. They take a terrible
toll."
When asked about the possibility that, as
forensic hand analysis becomes more common, paedophiles will start
wearing gloves, Black is adamant: "They won't. Most people who commit
crimes aren't very bright. They think they'll never get caught."
Case study: Dean Lewis Hardy
During
a trip to Thailand in 2004, Kent-based Dean Lewis Hardy took indecent
photos of four girls aged eight to ten years old, including images of
his hand touching them. Five years later, he was found guilty of
indecent assault after being identified through an analysis of the
images of his hands. He received a six-year sentence. Prosecutors said
it was the first case to use hand analysis. Black found Hardy's scars
matched that of the suspect, along with his freckle pattern and thumb
skin creases. "Scars and creases are accidental," Black explains.
"Freckle patterns are random, but their presence indicates a genetic
predisposition to freckle formation. Therefore, we had features of
different aetiology."
Left:
The left index finger of the offender is on the right, and that of the suspect (Dean Lewis Hardy) on the left. It highlights the freckles and a four-point punctuated scar.
The left index finger of the offender is on the right, and that of the suspect (Dean Lewis Hardy) on the left. It highlights the freckles and a four-point punctuated scar.
Middle:
The index finger of Hardy is on the right and the offender on the left. A filter has been used to make the freckles more obvious, then grouped into patterns that can be compared between the suspect and the offender.
The index finger of Hardy is on the right and the offender on the left. A filter has been used to make the freckles more obvious, then grouped into patterns that can be compared between the suspect and the offender.
Right:
Both images feature the thumbs of the suspect. The creases of the skin, nails and lunule - the crescent-shaped marking - have been outlined to assist the comparison with the images of the offender.
Both images feature the thumbs of the suspect. The creases of the skin, nails and lunule - the crescent-shaped marking - have been outlined to assist the comparison with the images of the offender.
In June 2016, Black was asked by Kent Police to work on
the case against Richard Huckle, one of the worst predatory paedophiles
in British history. Between 2006 and 2014, Huckle had groomed and
abused up to 200 Malaysian children, including babies, in Kuala Lumpur,
while masquerading as an English teacher and philanthropist. Images and
videos of his rapes and assaults had been shared with paedophiles on the
dark web.
In December 2014, National Crime Agency
officers arrested him when he arrived at Gatwick Airport to spend
Christmas with his parents, and found 20,000 indecent pictures and
videos on his laptop. Officers from the NCA's Child Exploitation and
Online Protection (CEOP) division viewed every picture and film clip.
The material was deeply disturbing: although 23 children would be
identified in the charges, the number of victims was believed to be far
higher because detectives found on his computer a ledger on which he
awarded himself "pedopoints" for 15 levels of abuse rated from "basic"
to "hardcore". He had also compiled a 60-page manual, "Paedophiles and
Poverty: Child Love Guide", which focused on selecting deprived victims
without being caught, and was found on his laptop. He'd planned to
publish it online and wanted to create a paedophile wiki guide. "I'd hit
the jackpot," he wrote, "in a three-year-old girl as loyal to me as my
dog, and nobody seemed to care."
When Black analyses
the backs of hands in footage she maps a grid of 24 cells, then looks
for identifying marks and highlights in the vein patterns
CEOP
officers selected material they felt was clearest and passed it to
Black. "Some of it was quite old, so it was degraded, but we didn't need
to study that," she says. "Advances in camera technology mean that
paedophiles are taking clearer pictures these days. It can make them
easier to identify." Even looking at this selection took her team a long
time. "It took us about four days to view it all, seeing what we could
use, isolating the parts to be used."In the end, Black's team were able to present
evidence to show that Huckle was likely to be the perpetrator, and as
the evidence mounted against him, as with Oketch, he changed his plea to
guilty. This resulted in the conviction of a man who judge
Peter Rook QC said had almost certainly blighted the lives of his victims and caused them severe psychological harm.
"The
significant thing about that case was the scale of the sentencing",
Black explains. "He was given 22 life sentences for 71 offences, which
was a way of the courts saying, 'We are serious about this, we are not
going to take it lying down.'" Black doesn't dwell on the horrors of
individual cases but prefers to talk about what can be done to stem the
sharing of child-abuse images online. "Can't our phones recognise parts
of a body and stop the image being taken?" she asks. "That's the
challenge I want companies such as Apple to take up, to stop technology
being a mechanism by which our children's innocence is being stolen.
Because, you know, the statistics say that one in six people have had
unwanted sexual attention as a child. One in six. I cannot think of a
crime that is more important. Can you?"
Richard
Benson is a London-based journalist and author. He wrote about Asem
Hasna's 3D-printed prosthetics for refugees in issue 07.17
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