Could a "lethality score" help prevent violent crime?

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Crime Prevention Databases

There are several different databases that collect information other than DNA. In the United States, the National Crime Information Center (NCIC) tracks information directly related to crimes, including records of convicted sex offenders, parolees and foreign fugitives. It also contains the names and activities of people involved in gangs or terrorist organizations. States tend to have a number of different databases with various types of crime-related information. Not only can they help to solve crimes by locating criminals, law enforcement officials can use the information contained in these types of databases to recognize trends.

In 2006, London's Metropolitan Police formed the Violent Crime Directorate, which seeks to target violent offenders. Within the directorate is the Homicide Prevention Unit, which attempts to ferret out the people most likely to commit violent crimes. The behavioral analysts within this unit create psychological profiles, using data gathered from the people who have come in contact with the potential criminal -- including mental health workers. Like DNA databases, this information can be used to solve existing crimes. But the intention is also to find criminals before they commit the crime and intervene in some way. Depending on the unit's findings, police could simply monitor the person. Or they could receive assistance from social or mental health services.

The Homicide Prevention Unit is in the process of creating a list of the most potentially dangerous people in London. Senior criminal psychologist Laura Richards stated "My vision is that we know across London who the top 100 people are. We need to know who we are targeting. Then we have the opportunity to stop something turning into a lethal event" [source: Bannerman].

The United States does not yet have a similar program in an official capacity, although some databases and programs are being developed in universities. Richard Berk, a professor of criminology and statistics at the University of Pennsylvania, has been working on a program that could be used to determine future murderers since 2006. His project was funded in part by the National Science Foundation. Using data from probation cases in Philadelphia, Berk and his colleagues chose around 30 different variables ranging from age at first crime to abuse as a child. They created an algorithm that weighs each factor and gives each offender a "lethality score." In this way, the parolees more likely to commit violent crimes could be monitored more closely.

A future crime database could roll information already being collected in various ways into one master database, starting with DNA and other identifying information (like fingerprints, retinal scans and face scans). It could also include personal data -- such as family, employment and economic status -- and histories of mental health and behavioral problems. While some of this information is already accessible by law enforcement officials, most of it is not. It takes a lot of money to collect all of the information and maintain the database. The NDIS costs hundreds of billions of dollars per year, and there is a huge backlog of data to be entered.

It would also take a lot of time to determine how to weigh specific elements, which elements were most important and how best to rank potential criminals. Finally, creating a future crime database would require some serious debate over privacy rights as well as the creation of many pieces of legislation. And as you might imagine, civil liberties groups aren't pleased with that idea. In the next section, we'll examine some of the criticisms of the existing databases and the challenges with creating a nationwide future crime database.