Forensic sciences definition

TLC is not quantitative and while it is a rapid and inexpensive means of obtaining exclusion of any relationship between heroin samples, it cannot be used with any reliability to confirm that two samples were once part of the same larger batch. HPLC is quantitative but does suffer from lack of definitive identification of each (chromatographic) peak. It is for these reasons that many forensic science laboratories use GC-MS for the comparison of heroin samples. 

A broad definition of the term forensic, according to Webster s New World Dictionary, is suitable for a law court or public debate. With the application of forensic science, one must demonstrate in court that the evidence analyzed has relevance to the case in question. The significance of evidence related to a case is often determined by whether the physical evidence has individual or class characteristic properties. Individual characteristics are properties of evidence that can be attributed to a common source with an extremely high degree of certainty. Class characteristics are properties of evidence that can only be associated with a group and never with a single source. (3)... 

Forensic chemistry exists where science and the law overlap. You might expect the marriage of science and the law to be an easy and natural one, but frequently it is not. The widespread perception is that science and the judicial system both exist to seek the truth, but that is an incomplete description. While tackling the definitions of scientific and legal truth is beyond the scope of this book, their intersection is at the heart of it, even when hidden behind chemical equations and reaction mechanisms. The term forensic refers to law enforcement, the judicial system, and the courts, and without/orens/c, there is no forensic chemistry. Accordingly, this brief chapter will provide you with the minimum legal context needed to explore forensic chemistry and the larger world of forensic science. 

Forensic science has evolved from an adjunct to medicine to a recognized profession— which raises the question of what defines something as a profession. A reasonable definition is that a profession is the practice of similar skills by a group of people who are paid to apply those skills in a more-or-less specified manner. A profession is differentiated from a job in that there is a governing... 

Figure 14.17 Example of uncertainty ellipses around the chromaticity coordinates obtained from fibers treated with a single dye. Sample identifiers are found in the next figure. Reproduced with permission from Hartshorne, A. W., and D. K. Laing, "The Definition of Colour for Single Textile Fibers by Microspectrophotometry," Forensic Science Internationai 34 (1987), 107-129. 

Harlshome, A. W., and D. K. Laing. "The Definition of Colour for Single Textile Fibers by Microspectrophotometry." Forensic Science International 34 (1987),... 

In its broadest definition, forensic science is the application of science to law. Many of the physical and spectroscopic techniques used in forensic science are covered in the earlier sections of this book. The series of cases described below will help to show how these techniques are used in forensic investigations. 

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