COMPUTER FORENSIC

Forensic Computer and Digital Analysis

Forensic Computer and Digital Analysis

General: Detailed history of forensic science

Computer forensics involves the preservation, identification, extraction, documentation and interpretation of computer data Forensic sciences were practiced before they were identified as forensic anthropology or even forensic science. Forensic science was first documented in France in 1910 with Dr. Edmond Locard's establishment of a center where scientists studying biology, physics, and medicine came together to examine evidence for criminal investigations. This group analyzed materials and shared resources in an attempt to reconstruct crime scenes.

Eventually known as a criminalistics laboratory, or crime lab, this model was followed in 1914 by the city of Montreal. The center in Montreal followed Locard's philosophy, called Locard's exchange principle, the foundation of the field of forensic science. Montreal's center was run by a physician and thus became known as a medico legal lab, a subspecialty of medicine. The structure of this model lab became popular, and in 1923, the first lab based on this model was established in the United States by the Los Angeles Sheriff's Department. In 1932, the newly established Federal Bureau of Investigation (FBI) set up its own lab, which could be accessed nationwide, although unlike the lab in France, contributions were minimal from different areas of science such as biology, chemistry, and physics (Clarke, 2003).

Over the last 100 years, experts have assisted with medico-legal investigations. Many physical anthropologists, especially from the Smithsonian Institute, acted as advisors to medico-legal officials through published articles and law enforcement bulletins during the 1930s and 1940s. In the 1960s, Lawrence Angel joined the Smithsonian staff and continued as a consultant for the FBI, including the launching of a training program for the forensic applications of skeletal biology.

An explanation of the scientific changes and methodologies/theories

The three main steps to a forensic investigation are the acquisition of the evidence, the authentication of the recovered evidence, and the analysis of the evidence. Each science has its preferred methodology. Thus chemists and experimental physicists can be described as typically working in laboratories and carrying out carefully controlled experiments predicting the outcome of various experiments and testing theories, although it is important to note that this is an oversimplification. These scientists do not use randomized controlled trials (RCTs), for example, which is the preferred methodology for the medical scientist concerned to evaluate the effect of a new drug or treatment program. RCTs are the gold standard for medical research, but they are not the gold standard for chemists and physicists. Similarly, in the area of crime science, it is the use of scientific method that is encouraged rather than the adoption of any particular experimental design or form of statistical analysis. The preferred experimental design is that judged most appropriate to address the hypothesis under investigation (Cornish, 2006).

The important methodological issues of science apply also to crime science—how to control for bias, how to facilitate replication, how to test theories and thus to establish knowledge. At present it is probably fair to say that, ...