Digital Evidence and Forensics
Computers are used for committing crime, and, thanks to the burgeoning science of digital evidence forensics, law enforcement now uses computers to fight crime.
Digital evidence is information stored or transmitted in binary form that may be relied on in court. It can be found on a computer hard drive, a mobile phone, a personal digital assistant (PDA), a CD, and a flash card in a digital camera, among other places. Digital evidence is commonly associated with electronic crime, or e-crime, such as child pornography or credit card fraud. However, digital evidence is now used to prosecute all types of crimes, not just e-crime. For example, suspects' e-mail or mobile phone files might contain critical evidence regarding their intent, their whereabouts at the time of a crime and their relationship with other suspects. In 2005, for example, a floppy disk led investigators to the BTK serial killer who had eluded police capture since 1974 and claimed the lives of at least 10 victims.
In an effort to fight e-crime and to collect relevant digital evidence for all crimes, law enforcement agencies are incorporating the collection and analysis of digital evidence, also known as computer forensics, into their infrastructure. Law enforcement agencies are challenged by the need to train officers to collect digital evidence and keep up with rapidly evolving technologies such as computer operating systems.
NIJ's Electronic Crime Program, which includes the Electronic Crime Center of Excellence, supports the development of tools to assist state and local law enforcement in combating e-crime and collect digital evidence. The program has five main focus areas:
- Mobile and Cellular Device Forensics Tools
- Digital Evidence Investigative Tools
- Digital Evidence Analysis Tools
- Digital Forensic Training
- Digital Forensics Standards and Capacity Building
 For a more complete discussion on the types of devices, see chapter one "Electronic Devices: Types, Description and Potential Evidence Electronic" in Crime Scene Investigation: A Guide for First Responders, Second Edition.