For MARCH 2004 issue

SCIENCE IN CRIME DETECTION-125

WHAT IS BIOMETRICS?

 ‑Dr. Anil Aggrawal

We have heard that recently the US is fingerprinting all the incoming travelers. This is in response to the increase threat of terrorism in the USA.

Very soon newer technologies will be emerging, whereupon, it won’t be necessary to fingerprint people at all. Similar identification will be done by such things as retina scan, iris scan etc. We will hear the term biometrics a lot during the coming years.

But first of all, what is Biometrics? Well, Biometrics is a way of using technology to identify people by reading the features of parts of their bodies. These parts can be iris, retina, palate, fingerprints, footprints, palm prints – anything that is unique in the human body. As such it is part of a social control system.

The basic idea is as old as humanity. People identified others from their tribe by their dress, facial markings and body tattoos. We identify each other by recognizing each other’s faces. But using technology to help recognize people has taken many forms. It began in the 1800s, when the police started taking fingerprints from criminals. Traditional ink fingerprints on paper cards are part of a low-tech information system for identifying individuals and storing information about them.

Finger imaging

Now new information technology reads fingerprints electronically. You put your finger onto a glass scanner plate like the ones in some supermarkets. The scanner reads your fingerprint and converts it into a digital code.

This finger imaging technology is already used a lot in Australia. Woolworths supermarkets use finger scanning to record attendance times of about 100 000 employees. More than 1400 bank ATMs are unlocked by finger scanning the Armaguard representative with a mobile scanner that plugs into the back of the ATM.

Finger scanning has some problems. Your fingerprint can be changed by a cut or scar, or worn down by heavy physical work. Then the technology might have trouble recognizing it. The scanner can also build up dirt and grease, making it hard for it to read properly.

From this onwards, we will try to give you some home activity too. So you can do this activity at home, and understand the concept much better. The activity for this month is as follows:

1. Using an ink pad and paper collect ten different fingerprints. Select people who have had different work experiences and are of different ages and sex. You can find such people in your neighborhood, and you will be happily surprised that they would be very keen to help you out. Examine the fingerprints carefully. Do this twice to see if you can accurately match people to fingerprints.

2. Try to explain why fingerprinting may not be as accurate as other forms of identification.

I may tell you that finger scanning is being used in a number of other applications today. Now we have smart guns, which will only shoot when the owner presses the trigger. The smart guns have sensors on them, which recognize only the fingerprints of the owner, and none else. So now if a dacoit snatches a gun from the police, or for that matter if anyone snatches gun from its owner, and tries to use it, he can’t because the gun will refuse to work. It will recognize the fingerprints only of the owner and not of the snatcher.

Finger scanning is just one of the biometric systems already in use. Two other systems read parts of the eye.

Retina scan

The retina scan bounces a beam of light off the inside of your eyeball and reads patterns of blood vessels there. This also has problems. The reader has to be very close to your eye, and has to be very accurately lined up. Also, some people feel worried about having a beam of light sent into their eye. It is actually very much like you being examined by your eye doctor through an ophthalmoscope. He throws a beam of light at the back of your eye, and studies your retina. Retinas of all people have distinctive blood vessel pattern, and from this one can identify people properly.

Iris technology

The other part of the eye that can be read is the iris. This is the colored part of the eye, and everyone’s is different. This is easier to read than retina scans because it involves standard video technology, and is recorded from further away, about 22 centimeters away from the actual eye.

Iris recognition technology was pioneered by John Daugman, of Cambridge University. It identifies people by the unique patterns of the iris — the colored ring around the pupil of the eye. This new and wonderful technology is fast and non-invasive.

This technology will now used at London’s Heathrow Airport too. This new iris recognition technology enables selected passengers to look into a video camera at the passport control checkpoint and have their identity verified within seconds. The Heathrow program will be the first large-scale passenger processing trial in the world to rely entirely on biometric identification.

Passengers taking part in the Heathrow trial will be pre-cleared by the U.K. Immigration Service. Passengers will still be required to carry passports but their permission to enter the U.K. will be based on the real-time verification of their iris pattern. The program is aimed at expediting passenger arrivals and reducing operating costs. Up to 2,000 North American citizens — customers of Virgin Atlantic and British Airways who travel frequently to the United Kingdom — will be able to enroll in the trial. The so-called “one-stop” identification process uses iris-recognition technology to identify passengers at all steps in the travel process. Powerful software translates the iris pattern into a frequent-flier number or passport number, and then communicates this with airport and airline computers to simplify check-in, baggage check, boarding and passport control.

The system being used at Heathrow is called JetStream Passenger Processing and was developed by McLean, Va.-based EyeTicket Corp., in partnership with Simplifying Passenger Travel, an interest group of the International Air Transport Association. The association, formed to develop “one-stop” passenger processing for airlines and airports, includes more than 40 major airports, airlines, immigration authorities, and technology suppliers around the world, including British Airways, United Kingdom Immigration Service and Virgin Atlantic Airways. EyeTicket demonstrated the system at the International Air Transport Association’s World Air Transport Summit in Madrid some months back. After this demonstration, Thomas Windmuller, director of Simplifying Passenger Travel, said in a statement, “I expect we will see other trials launched at major airports throughout the world.” This technology can be used in a number of other applications as well, as can be seen in the accompanying photograph. Here a person is opening a lock by looking at it. The lock recognizes only the eye patterns of the owner, and will only open when the owner looks at it. No fear of lost keys etc! Just imagine, how convenient it can be.

Other biometric systems

Other biometric systems already being used include:

measuring the geometry of your hand

video recognition of your face

voice recognition.

These all have disadvantages:

hand shapes can change or be affected by an accident

people with similar faces can be mixed up

people can change how they look

people’s voices can change if they’re sick or upset

limitations of the technology. One has to develop very complicated software to be able to do all this.

Animal biometrics

Biometrics hasn’t just been used to identify people. Other animals have things about their bodies that are unique as well. Many animals have noses that have slightly different patterns on them, just like people have different fingerprints. Sometimes people use things like animal nose prints to identify individual animals.

Nose printing

In the USA pedigree show dogs are nose printed to make sure there’s no pre-show switching.

In Africa conservationists trying to help save the gorillas use nose prints to identify each gorilla, and zoos sometimes use nose prints to identify some of their animals.

In some parts of the world livestock are nose printed. In Texas show lambs are nose printed. In Japan nose prints are used to identify cows. Cows cost a lot of money in Japan. To make sure you get what you paid for, each top quality cow comes with a set of papers that includes a nose print. This also helps make a positive identification in case a cow is stolen. This information about Japanese cow nose prints may appear amazing to you, but it is true, and this is a good example of biometrics.

More and more, biometrics is being used to identify animals. As well as biometrics, genetic testing is starting

to be used to identify animals.

There is an activity involved here too. If you have a dog, try to take his nose prints. Ensure you use non-toxic ink and gain the permission and supervision of the owner (if you do not have a dog). Let me know on how easy or hard it was for you to differentiate the dogs.

Genetic ID

Genetic identification involves testing a person’s or animal’s DNA. Everyone has their own unique genetic blueprint. Genetic technology now lets people read the DNA of a person and positively identify them. Hence genetic identification is part of a control system.

DNA testing is used for many purposes. It can be used to:

find out who is the biological father of a child

help identify human remains, like an unidentified body. It is often used for criminal investigations.

Wildlife conservation

Genetic identification can be used to help with wildlife conservation. For example, researchers use genetic identification to identify humpback whales. In the past, they took photos of the tail of each whale as it swam past. Each whale was identified by the shape of the tail and its markings. But this method was not always accurate.

Now researchers in Byron Bay pick up from the water hundreds of tiny flakes of skin that naturally fall off when the whales surface or slap their tails. They analyze the flakes and read each whale’s unique DNA. Now they can keep track of exactly which whales are on the move, where they go, how long they live and so on.

The most basic information that can possibly exist about a person is the actual genes that they’re built of, and that make them who they are. One way of looking at this issue is that DNA is the most personal information that there is.

Genetic identification is often called genetic tagging, but it is not really tagging. Tagging involves people marking someone or something to identify it. Genetic identification is different. It’s like biometrics, it involves reading something that naturally exists about a person or animal, in this case its DNA.

DNA in criminal investigation

If someone commits a crime and leaves behind something from their body, it can be analyzed to work out the DNA of that person. What they leave behind might be some hair, blood, saliva or semen.

Once the police know the DNA of the person they are looking for, they can test their suspects. When they find someone whose DNA is exactly the same as the DNA left behind, they know they’ve got the person they’re after.

At the end of 2000 police in Sydney arrested a man for the murder of a young woman who was found dead in Darlinghurst three years before. The police took samples of saliva from the men who lived in a boarding house that backed onto the lane where the woman was found. One of the samples matched, and the police made their arrest.

At the moment, the police in New South Wales don’t have the power to force lots of people to have DNA tests. In this case the men gave their samples voluntarily. So why did the person they arrested agree to give a sample?

A similar thing happened earlier in 2000, after an elderly woman in the town of Wee Waa was raped. Because it was only a small town, the police asked all the men to volunteer to give a sample for DNA testing. Almost everyone did. The feeling in the town was that if you didn’t want to have the DNA test you must have something to hide. But a few men refused, even though they had nothing to do with the crime.

Captions to the figure supplied

finger.jpg: This is how the fingers are scanned in order to expedite the fingerprint recognition.

eye.jpg: Evan Smith, a senior vice president of EyeTicket Corp., peers into a sensor that serves as a futuristic lock on a door at the Charlotte, N.C., airport. His eye is the key.

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Dr. Anil Aggrawal, M.D. Professor of Forensic Medicine Maulana Azad Medical College New Delhi‑110002