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Fire Debris Analysis
von: Eric Stauffer, Julia A. Dolan, Reta Newman
Elsevier Trade Monographs, 2007
ISBN: 9780080556260 , 672 Seiten
Format: PDF, ePUB, OL
Kopierschutz: DRM
Preis: 83,95 EUR
CHAPTER 2 History
“The moments of the past do not remain still; they retain in our memory the motion which drew them towards the future, towards a future which has itself become the past, and draw us on in their train.”
Marcel Proust, French writer, essayist, and critic (1871-1922)
2.1 PREAMBLE
2.1.1 Why Learn Some History?
It is important to understand where fire debris analysis comes from and how it evolved into today’s technology and practice. Looking back at the history of a scientific branch can be quite interesting, not to mention quite shocking. How predecessors did things makes one realize how much progress has been made. It also helps the modern criminalist to orient future research and developments in forensic sciences.
These are some of the reasons why the authors strongly believe it is important for every fire debris analyst to have a basic knowledge of the history of current practice. This chapter is intended to provide this information. When desired, the reader is encouraged to read further into the articles cited throughout the text to obtain more information about the past. Researching literature in the past is not always an easy task. Fortunately, the bulk of forensic sciences are quite young (about 120 years old) and fire debris analysis even younger (about 70 years old). Thus, the task is much easier than researching ancestral Roman Empire customs. The chapter limits the extent of the information presented to major milestones in fire debris analysis as well as to some noteworthy text extracts, which are often amusing. The research conducted to gather this material has been relatively thorough, however, it is not, and probably can never be, fully comprehensive.1 Also, as a general rule, the older the information, the less reliable it is. Whenever available, controversies in history of fire debris analysis have been presented. The reader is also invited to return to this chapter once proficient in fire debris analysis, as it will make the reading much more entertaining.
2.1.2 Starting with Bread Crumbs
In 1945, H. Rethoret wrote in his fire investigation book [1]:
The sense of taste can also be used to good advantage. Prior to relying on the sense of taste, it has been recommended that fresh breadcrumbs be chewed for a while and then expectorated in order to get a clean taste in one’s mouth. The suspected place is then lightly touched with a piece of bread which, in turn, is chewed for a while. The taste of combustible material is then noted, even if only a slight trace of it adheres to the bread. While this is an unappetizing method, it is useful. Practically everyone can recall from time to time tasting kerosene if their food accidentally touched that liquid.
Although the sniffing of ashes by fire investigators was very common at the beginning of the century, and is still somewhat common today, the tasting of possible ignitable liquid was not so common. Rethoret’s text is as good as it gets in this regard. A more “scientific” approach than the one offered by Rethoret is presented by Battle and Weston in 1954 [2]: “Investigators can quickly learn to recognize the odors of various flammable liquids by placing small amounts in wide-mouthed glass jars. By shutting their eyes, opening a jar, and guessing as to its contents they’ll soon build up an experience which will permit them to make prompt identification.”
The same year, Myren publishes his book in which he presents a case [3]: “In the burning of a dry goods store in North Carolina, one of the firemen noted that some of the stock of clothing appeared to be saturated with kerosene. He sealed several of the garments in a can, marked the can so that he could identify it, and turned it over to the solicitor. […] Imagine the effect on the jury when the odor of kerosene from that can reached their nostrils.”
Apparently, the olfactory examination was not only good for the fire investigator, but it was also excellent for convincing a jury during court proceedings.
The reliance on one’s own sense of smell was a recommended practice from the beginning of fire investigation and is found in many early books treating the topic. However, one might think that with the progresses that started in the early 1940s and the advent of gas chromatography in 1960, the reliance on olfactory examination would be confined to the field investigator and to a very preliminary examination at the laboratory (see Chapter 10). Unfortunately, in 1978, although fire debris analysis was quite well-developed, it was still possible to find marginal procedures presented in forensic books such as [4]:
Infrared spectrophotometers are also used in the crime laboratory for identifying unknown liquids used as accelerants in cases of arson. Sometimes, however, quick tests can be easily done by investigators with only a limited knowledge of laboratory techniques.
TEST 1 Any object suspected of containing a flammable substance may be heated in water to a temperature of 70°C. When the container is opened, it is often possible to determine the type of flammable material by its odor.
TEST 2 A suspected substance may be broken into pieces and put into a distillation flask with a little water. The flask is then heated so that the material inside is distilled. The fractions passing off may be roughly identified by odor—gasoline being the more volatile will come first, then kerosene a few fractions further on.
In 1978, infrared spectrometers were not commonly used at the crime laboratory to identify ignitable liquid residues (ILR), and, though a quick olfactory examination may prove useful with all samples, the procedures presented in the cited text should not be applied to fire debris samples.
2.1.3 The Very Beginning
One of the difficulties encountered in reconstructing an accurate timeline for the development of fire debris analysis is that there are many chronological inconsistencies in the information presented in the different publications related to fire investigation. As presented in the previous paragraph, setbacks (old and obsolete techniques published in newer books) are often found. Prior to the 1940s, it is extremely difficult to find any books or articles that describe any possible examination for the identification of the presence of ILR or even suggest the collection of debris.
In his Manuel de police scientifique from 1911, Reiss, founder of the now School of Criminal Sciences of the University of Lausanne in Switzerland, described the technique used to search for petroleum products in fire debris [5]. This is the oldest account of distillation techniques applied to fire debris analysis found by the authors, and the methods were well ahead of Reiss’ time.
In 1923, Locard, in his manual on scientific police, referred the reader to the text of Reiss [6]: “We found traces of the fuel oil that was used to set the fire (Reiss).”2 No other mention of the possible collection and analysis of fire debris was given.
In 1938, Bischoff gave a great explanation regarding the presence of ILR at the scene, their detection, and collection [7]:
A considerable portion of the liquid cannot be absorbed by the substrate onto which it is poured so the excess flows onto the floor and forms puddles. The liquid also follows declivities and seeps in cracks in the wood flooring, between floor tiles, and even penetrates the ground. These are the reasons why we can almost always retrieve sufficient quantities of this liquid in order to characterize it and to demonstrate its use. It is not rare that, after completely removing the debris, when lifting a wooden floor or digging up the ground we can perceive an odor characteristic and revealing of the ignitable liquid used by the arsonist. One must remember this smell when collecting debris that will be forwarded to a chemist for analysis performed in order to isolate and characterize the liquid.3
In 1949, Turner advised the criminalist to secure liquids or samples that are believed to be impregnated with an inflammable material and to send them to the forensic laboratory for analysis [8]. He also recommended collecting undamaged or unimpregnated samples as controls. Interestingly, no description of any analytical techniques applied to fire debris analysis is found in his book.
It is important to remember that fire investigation is as contemporary as forensic sciences. As a matter of fact, in the United States, one of the oldest published articles relating to the possible investigation of fires is a letter written by Thomas Edison to the New York Board of Underwriters and dated 1881 [9]. Edison warns them about the possible danger of electricity in starting a fire. The science of fire investigation probably started prior to this date and likely outside the United States, however no formal publications were retrieved from that time.
2.1.4 Evolution of Fire Debris Analysis
With the development of more formal forensic sciences and the progress made in chemistry and subsequently in...
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