Regional Computer Forensics Laboratories (RCFL) -- of which there are currently 14 -- send out investigators to perform computer forensics at the request of local law enforcement. Computer forensics use digital evidence -- such as files found on a computer or network storage device, or an electronic document -- to build a case in a law-enforcement investigation in the same way traditional investigations use fingerprints and other physical evidence.
The FBI's RCFLs have participated in a range of investigations, such as terrorism, environment crime, public corruption, homicides, rapes, crimes against children and fraud.
The FBI provides startup and operational funding, training and equipment for the RCFLs, while state, local and federal agencies assign personnel to work as examiners. Examiners collect digital evidence at crime scenes, conduct examinations on electronic devices and testify in court about what they've found.
Sometimes digital evidence can tell the story of a crime or incident in ways traditional evidence can't. For example, the FBI's RCFL in Silicon Valley aided in the investigation of a San Francisco Bay oil spill by discovering that navigation charts on a computer had been changed after the crash, according to the FBI. This hinted at foul play in a way physical evidence likely never would have.
In another case in Texas, RCFL examiners helped local authorities in a case involving a disgruntled employee who was dismissed from a nonprofit and then erased vital computer files in retaliation.
During fiscal year 2009, 689 different law-enforcement agencies requested assistance from the labs, which conducted 6,016 digital examinations. The investigation required the processing of 2,334 terabytes of information, according to the FBI.
In addition to aiding with live investigations, the labs also provide training to state and local law enforcement on how to take initial steps when arriving at a crime scene to secure digital evidence. In fiscal-year 2009, RCFLs trained 5,404 officers in digital forensics techniques and tools.