Law Enforcement can be called the birthplace of biometrics. This is where systematic attempts of human identification using fingerprints took place during criminal investigations. That time, however, they were targeted towards the identification of criminals and other people at a crime scene. Fingerprints, collected from a crime scene, were leveraged to investigate the crime and people involved by matching them against the other prints. Other prints involved fingerprints from the suspects or taken from existing collection. Despite the extensive use in Law Enforcement, biometrics is not limited to crime investigation now. It has become an omnipresent method of identification wherever human identification is a need. From fingerprint attendance systems at office doors to fingerprint unlock on smartphones, biometrics is the underlying technology that makes identification of human beings possible.

In this article, we take a look at how biometric identification is doing at its place of origin, i.e. the law enforcement and how it has improved since its early days.

Law enforcement, as the name suggests, is the process of ensuring that laws enacted by the government are in effect and followed as they are codified. Governments put dedicated agencies to ensure that laws stay enforced and people who try to break them or disrupt the order, could be brought to justice. Bringing people to justice requires their accurate identification and evidences that prove their involvement in breaking the laws. To escape this process, people try to dodge Law Enforcement Agencies by changing identities, names and looks. Escaping law enforcement agencies was more or less easy as before the inception of biometrics. Criminals do all kinds of forgery to dodge police and law enforcement agencies. They change looks, places, manipulate or fake identities, counterfeit documents, etc. which do not require much effort because of use of technology.

Law enforcement agencies are always in a great need of precise and quick identification of people specially suspects and criminals. Error in identification can result in wrong people suffering and even losing their lives. For example, if police opens fire on a wrongly identified people, it can result in innocent people getting hurt or losing their lives. That is not it, without accurate identification, actual purpose of law enforcement, i.e. justice, cannot be served.

1. For identification of know criminals, suspects or terrorists. For example, people who are serving their sentence or undergoing the judicial process.
2. For crime investigation, in which forensic people are continually involved to collect and match biometric patterns collected from crime scenes.
3. Surveillance, intelligence gathering and Security.
4. Above three use cases can be called core purposes of law enforcement. Biometrics, however, can also be used in identification of people involved in law enforcement, e.g. office staff, service providers, third party vendors, etc.

Booking of new criminals, who are not yet on biometric radar of law enforcement agencies, gives them a chance to collect their biometric data and put it in their system. It enables law enforcement agencies to track and identify them in the future if they continue their criminal activities. But that is not it, collection of biometric data during criminal booking can be used in many other activities if a correction center or prison uses biometric systems for prison security.

Correction centers play an important part in serving actual purpose of the law enforcement. People serve their sentence and learn to work and adjust with the civil society. Tracking and security of inmates serving their sentence is a crucial task in a prison. Since in some prisons, number of inmates can grow very large, keeping track of each prisoner can be challenging. Fortunately biometric applications can address multiple challenges that are faced during the day to day operations in prisons. Prisons are special institutions and their needs of safety, security and surveillance can vastly differ from other civil institutions. Jail personnel have to make sure that prisoners are secure, traceable and they do not hurt each other as well as the prison officers.

Biometric applications using face biometrics and fingerprint recognition can help prison officers maintain law and order within the jails and correction centers. Tracking of inmates during their movements within the facility is one of the many challenges, which biometric applications can easily address. Inmate movement from one point to another can cause a problem if an inmate does not reach the destination in expected time. Biometric scan at both the ends can solve this problem.

Biometric traces left behind by the people involved in a crime can be the greatest mean of taking a crime investigation forward. These prints are the first thing to look for when such an incident occur. Securing a crime scene is a standard practice to save evidences and prints from contamination. That is why we see people are not allowed beyond a certain distance at a crime scene as they may contaminate (intentionally or unintentionally) human prints by touching things or stepping on them. Collection of these human prints is the next step, which is done by forensic experts. These prints are secured and taken to forensic labs to compare them with existing or newly acquired biometric scans of suspects.

Crime scene investigation, collection and processing of human biometric identifiers are the standard procedures done by law enforcement for resolving crimes, and they are not new practices. By the mid-twentieth century, police had started using fingerprints to associate criminals with their crime history and identify people at the crime scene using latent fingerprints. Early biometric implementations from law enforcement agencies like Federal Bureau of Investigation (FBI) were all manual. They used fingerprint cards to collect, process and store fingerprints. In 1980s, when computer and optical imaging started spreading its wings, efforts of computerized fingerprint recordkeeping started. This was also the time when U.S. law enforcement agencies began to implement Automated Fingerprint Identification System (AFIS).

This is another important activity performed by law enforcement agencies to maintain law and order. Biometrics applications are increasingly being leveraged to preform surveillance. As the world increasingly gets digitally and physically connected, level of threats also increases. Numbers of cyber-security and terrorist incidents have dramatically increased in the recent years. These threats can originate from anywhere in the world and can affect a country negatively. Rival countries secretly organize terrorist and cyber attacks against each other and law abiding citizens have to pay the price. Mass surveillance has become a necessity for law enforcement agencies to identify and stop threats beforehand. Mass surveillance also helps with intelligence gathering that assists law enforcement and national security agencies stop crimes and terrorist activities.

In many countries, law enforcement agencies are introducing smart traffic cameras that can do much more than just recognizing number plates. These high resolution cameras can recognize people sitting in the vehicle and raise an alert if the subject is under surveillance. Digital surveillance is another form of surveillance in which internet and communication traffic is monitored for suspicious activities. Surveillance activities hamper privacy, however, they are made legal by the government by enacting appropriate laws. For example, in the United States Communications Assistance For Law Enforcement Act, gives the federal law enforcement agencies authority to monitor phone calls and Internet traffic (web traffic, emails, web traffic, instant messaging, etc.) in real time.

Law enforcement agencies have had close association with fingerprints for quite a while, however modern biometric technology makes use of all sorts of modalities and even mix them to curb inadequacies and get better results. Other than fingerprint biometrics, facial recognition, iris recognition, gait analysis, voice recognition, DNA profiling, etc. are commonly used biometric modalities.

Fingerprints are among the first biometric modalities used at law enforcement. It has historical association with law enforcement in forensic applications and continues to be one of the important modalities used in modern times. Fingerprint recognition methods leverage unique pattern formed by friction ridges on fingertips to identify people. Technology assisted scanning and matching has greatly reduced human efforts required for the job. Present day law enforcement agencies are not just about stopping crimes. They do a lot of other things like civil identification, employment background check, and management of biometric data. FBI has one of the largest biometric databases in the world, which has civil as well as criminal biometric data.

The bureau have been using IAFIS system that primarily uses fingerprint for identification, however, the Next Generation Identification (NGI) System will also be able to perform advanced lookup, incorporating palm print, iris, and facial identification.

Facial recognition is one of the biometric modalities which is increasingly getting popularity in civil as well as law enforcement applications lately. Many banks and financial service institutions are enabling customers to authenticate their transaction with a unique facial authentication method popularly known as Selfie Pay. It is also being increasingly used in surveillance applications by governments of several countries. In facial recognition applications, unique configuration of a person’s facial features is used to accurately identify them. In mass surveillance applications, stills to analyse are usually taken from the surveillance videos. Both the Department of Homeland Security and DARPA are heavily funding research into facial recognition systems. A program known as Human Identification at a Distance program ran by the Information Processing Technology Office, is capable of identifying a person at up to 500 ft. (150 m) by their facial features.

In another example, China’s Golden Shield Project, aka National Public Security Work Informational Project, is aimed at building nationwide network security infrastructure. Several tech giants like General Electric, IBM and Honeywell have been working on the project in association with the Chinese government. This project aims to install millions of surveillance camera throughout the country that will be backed by an advance facial recognition system and video analytics. Governments of many countries also use traffic and other public cameras for performing facial recognition surveillance on people, however, it is never officially accepted.

Since government agencies have ability to surveil communication channels, they have technology that can intercept the communication recognize the speech as well as speaker with the use of voice recognition technology. Voice recognition makes it possible to match a voice sample against already established identities on the basis of voice pattern. Voice sample can be captured from any human or non-human source with a simple audio recorder. Stringray Phone Tracker and similar devices can intercept GSM communication content and this content can be fed to a voice biometric system to identify a subject under surveillance. International voice communication, especially taken place between the people of rival countries, is often unveiled to gather intelligence and avoid undesirable incidents.

DNA profiling or DNA fingerprinting is a technique, in which unique characteristics of an individual’s DNA are mapped. In forensic science, DNA profiling is a commonly used method to identify unidentified individuals. DNA is found to be 99.9% similar in all human beings, still remaining .1% DNA is quite enough for distinguishing one individual from another. Unlike other biometric methods, DNA profiling require physical sample from human body and considered highly invasive biometric method. When a DNA evidence is found at a crime scene, it is matched against the newly acquired DNA profile of suspects or probable profiles which are already on the database. Developed in 1985, DNA profiling has helped law enforcement agencies solve complex cases in which no other strong evidences except DNA were found.

Some criminal cases have been solved solely on the basis of DNA profiling of human remains found on the crime scenes. In a murder case, a DNA evidence that was collected in 1984, helped law enforcement agencies brings the murderer to justice after 32 years.

Law enforcement agencies rely heavily on the accurate identification of people and it can be efficiently done with the use of biometrics. Use of biometrics is not a new practice in law enforcement; however, it was not as technologically advance as present day applications. Rise of computing and electronics have greatly assisted biometric applications to become faster, more secure and cheaper. These qualities have brought them to civil identification applications as well.

Exercise of human identification on the basis of anatomical characteristic has been in use since 19th century in law enforcement applications. Modern biometric applications can be used at various fronts in law enforcement applications. Use of biometrics has become a necessity in today’s complex world. Present day biometric applications at law enforcement applications are used from solving a crime mystery to ensure national security. Mass surveillance using facial recognition, gait analysis and voice recognition is performed to gather intelligence and stop any undesirable incidents. It is not doubt that biometrics in the future of identification, and with law enforcement, it is the future of peaceful civil society as well.