Eric Lock

Intelligence-led crime scene processing. Part I: Forensic intelligence

Forensic science is generally defined as the application of science to address questions related to the law. Too often, this view restricts the contribution of science to one single process which eventually aims at bringing individuals to court while minimising risk of miscarriage of justice. In order to go beyond this paradigm, we propose to refocus the attention towards traces themselves, as remnants of a criminal activity, and their information content. We postulate that traces contribute effectively to a wide variety of other informational processes that support decision making in many situations. In particular, they inform actors of new policing strategies who place the treatment of information and intelligence at the centre of their systems. This contribution of forensic science to these security oriented models is still not well identified and captured. In order to create the best condition for the development of forensic intelligence, we suggest a framework that connects forensic science to intelligence-led policing (part I). Crime scene attendance and processing can be envisaged within this view. This approach gives indications about how to structure knowledge used by crime scene examiners in their effective practice (part II).

Intelligence-led crime scene processing. Part II: Intelligence and crime scene examination.

A better integration of the information conveyed by traces within intelligence-led framework would allow forensic science to participate more intensively to security assessments through forensic intelligence (part I). In this view, the collection of data by examining crime scenes is an entire part of intelligence processes. This conception frames our proposal for a model that promotes to better use knowledge available in the organisation for driving and supporting crime scene examination. The suggested model also clarifies the uncomfortable situation of crime scene examiners who must simultaneously comply with justice needs and expectations, and serve organisations that are mostly driven by broader security objectives. It also opens new perspective for forensic science and crime scene investigation, by the proposal to follow other directions than the traditional path suggested by dominant movements in these fields.

Analytical profile of 4-methylthioamphetamine (4-MTA), a new street drug.

The analytical properties for a new street drug, 4-methylthioamphetamine (4-MTA), are presented. This new compound was found in tablets sold on the illicit market in the Netherlands and Switzerland in 1997 and 1998. The intermediate 1-(4-methylthiophenyl)-2-nitropropene was also found in a clandestine laboratory in the Netherlands in January 1997. In this study, reference standards were prepared and characterized. The ultraviolet, infrared and nuclear magnetic resonance spectral properties as well as the chromatographic and mass spectrometric (MS) data are reported.

A New Europium Chelate as a Fluorescent Dye for Cyanoacrylate Pretreated Fingerprints—EuTTAPhen: Europium ThenoylTrifluoroAcetone Ortho-Phenanthroline

The use of luminescent dyes to enhance fingerprints developed with cyanoacrylate is now a well established procedure in most fingerprint laboratories. Misner, Wilkinson and Watkin [1] have proposed a new fluorescent dye using an Europium complex (TEC). The purpose of the present paper is to report on further studies of this dye (TEC) and some analogues. Preliminary tests on cyanoacrylate pretreated fingerprints showed that a formulation of EuTTAPhen (Europium ThenoylTrifluoroAcetone ortho-phenanthroline) was the most efficient complex giving the best luminescence intensity of the treated fingerprints, a Stokes shift of 262 nm and reduced practical drawbacks.

Identification and quantification of amphetamine and analogues by capillary zone electrophoresis

A free zone capillary electrophoresis (CZE) system, with diode array detection, was used in the analysis of ephedrine and 9 amphetamines. The method was quantitative, offering better resolution than gas chromatography (GC), without the need for sample derivatisation. Under hydrodynamic injection, the concentrations of drug at which detection limits were reached lay between 13 and 68 micrograms/ml, with detection at 214 nm, these limits being of the same order of magnitude as those of GC. Analysis of casework samples by the two methods demonstrated the advantages of CZE with diode array detection over conventional GC for amphetamine identification and quantification.

Utility of the clue — From assessing the investigative contribution of forensic science to supporting the decision to use traces

In an attempt to grasp the effectiveness of forensic science in the criminal justice process, a number of studies introduced some form of performance indicator. However, most of these indicators suffer from different weaknesses, from the definition of forensic science itself to problems of reliability and validity. We suggest the introduction of the concept of utility of the clue as an internal evaluation indicator of forensic science in the investigation. Utility of the clue is defined as added value of information, gained by the use of traces. This concept could be used to assess the contribution of the trace in the context of the case. By extension, a second application of this concept is suggested. By formalising and considering, a priori, the perceived utility of using traces, we introduce the notion of expected utility that could be used as decision factor when choosing which traces to use, once they have been collected at the crime scene or from an object in the laboratory. In a case-based approach, utility can be assessed in the light of the available information to evaluate the investigative contribution of forensic science. In the decision-making process, the projection or estimation of the utility of the clue is proposed to be a factor to take into account when triaging the set of traces.