Forensic Analysis on the Cutting Edge: New Methods for Trace Evidence Analysis

Preface.

Foreword.

Contributors.

1. All that Glitters Is Gold! (Robert D. Blackledge and Edwin L. Jones, Jr.).

1.1 What Is Glitter?

1.2 The Ideal Contact Trace.

1.2.1 Nearly Invisible.

1.2.2 High Probability of Transfer and Retention.

1.2.3 Highly Individualistic.

1.2.4 Quickly and Easily Collected, Separated, and Concentrated.

1.2.5 Easily Characterized.

1.2.6 Computerized Database Capability.

1.3 Characterization Methods.

1.3.1 Color.

1.3.2 Morphology.

1.3.3 Shape.

1.3.4 Size.

1.3.5 Specifi c Gravity.

1.3.6 Thickness.

1.3.7 Cross Section.

1.3.8 Infrared Spectra.

1.3.9 Raman Microspectroscopy.

1.3.10 Scanning Electron Microscopy/Energy Dispersive Spectroscopy.

1.4 Glitter as Evidence in Criminal Cases.

References.

2. Forensic Analysis of Automotive Airbag Contact—Not Just a Bag of Hot Air (Glenn D. Schubert).

2.1 History of Airbags.

2.2 How Do Airbags Work?

2.3 Types of Forensic Evidence to Look for.

2.4 Airbag Case Reports and Examples.

2.5 Changes that Are Occurring.

2.6 Final Discussion.

References.

3. Ink Analysis Using UV Laser Desorption Mass Spectrometry (John Allison).

3.1 Introduction.

3.2 The Instrumentation.

3.3 The Analyte Target Molecules.

3.4 LDMS for the Analysis of Dyes in Pen Inks.

3.5 Related Applications.

3.6 LDMS Analyses that "Don't Work."

3.7 Conclusions.

Acknowledgments.

References.

4. Condom Trace Evidence in Sexual Assaults: Recovery and Characterization (Wolfgang Keil).

4.1 Introduction.

4.1.1 Forensic Signifi cance.

4.1.2 Production, Sale, and Use of Condoms.

4.1.3 Condom Production.

4.2 Examination for Condom Residue Traces.

4.3 Forensic Evaluation of the Substances and Examinations.

4.4 Case Studies.

References.

5. Latent Invisible Trace Evidence: Chemical Detection Strategies (Gabor Patonay, Brian Eckenrode, James John Krutak, Jozef Salon,and Lucjan Strekowski).

5.1 Introduction.

5.2 Latent Bloodstain Detection.

5.3 Fingerprint Detection with Near-Infrared Dyes.

5.4 Pepper Spray Detection.

5.4.1 Pepper Spray Detection Using Near-Infrared Fluorescent Dyes.

5.4.2 Pepper Spray Detection Using Chemical Derivatization.

References.

6. Applications of Cathodoluminescence in Forensic Science (Christopher S. Palenik and JoAnn Buscaglia).

6.1 Introduction.

6.2 Theory.

6.2.1 Luminescence Terminology.

6.2.2 Electron Source.

6.2.3 Cathodoluminesence.

6.2.4 Limitations.

6.3 Instrumentation.

6.3.1 Electron Source.

6.3.2 Microscope.

6.3.3 Camera.

6.3.4 Spectrometer.

6.3.5 SEM-CL.

6.4 Techniques and Forensic Considerations.

6.4.1 Instrumental Conditions.

6.4.2 Sample Preparation and Preservation.

6.4.3 Image Collection.

6.4.4 Spectral Collection.

6.4.5 Luminescence Fading.

6.4.6 Sample Alteration.

6.5 Luminescent Minerals.

6.5.1 Calcium Carbonate Group.

6.5.2 Feldspar Group.

6.5.3 Quartz.

6.5.4 Accessory Minerals.

6.6 Forensic Applications.

6.6.1 Screening and Comparison.

6.6.2 Identifi cation.

6.6.3 Authentication.

6.6.4 Provenance.

6.7 Geological Samples: Soil and Sand.

6.8 Anthropogenic Materials.

6.8.1 Cement and Concrete.

6.8.2 Slag, Fly Ash, and Bottom Ash.

6.8.3 Glass.

6.8.4 Paint.

6.8.5 Duct Tape.

6.9 Conclusions and Outlook.

Acknowledgments.

References.

7. Forensic Application of DARTTM (Direct Analysis in Real Time) Mass Spectrometry (James A. Laramée, Robert B. Cody, J. Michael Nilles, and H. Dupont Durst).

7.1 Introduction.

7.2 Experimental.

7.3 Drug and Pharmaceutical Analysis.

7.3.1 Confi scated Samples.

7.3.2 Endogenous Drugs.

7.3.3 Drug Residues on Surfaces.

7.4 Samples from the Human Body.

7.4.1 Fingerprints.

7.4.2 Bodily Fluids.

7.5 Condom Lubricants.

7.6 Dyes.

7.6.1 Self-Defense Sprays.

7.6.2 Currency-Pack Dye.

7.7 Explosives.

7.8 Arson Accelerants.

7.9 Chemical Warfare Agents.

7.10 Elevated-Temperature DART for Material Identifi cation.

7.11 Glues.

7.12 Plastics.

7.13 Fibers.

7.14 Identifi cation of Inks.

7.15 Conclusion.

Acknowledgments.

References.

8. Forensic Analysis of Dyes in Fibers Via Mass Spectrometry (Linda A. Lewis and Michael E. Sigman).

8.1 Introduction.

8.2 Conventional Fiber Color Comparison Methods Employed in Forensic Laboratories.

8.3 Shortcomings Associated with UV–Vis Based Comparative Analysis for Trace-Fiber Color Evaluations.

8.4 General Overview of Modern Dye Ionization Techniques for Mass Analysis.

8.5 Trace-Fiber Color Discrimination by Direct ESI-MS Analysis.

8.6 Examples of Negative Ion ESI-MS Analysis of Colored Nylon Windings.

8.7 Examples of Tandem Mass Spectrometry (MS/MS) Applications to Elucidate Structure.

8.8 LC-MS Analysis of Dyes Extracted from Trace Fibers.

8.9 Proposed Protocols to Compare Trace-Fiber Extracts.

8.9.1 Direct Infusion MS/MS Protocol.

8.9.2 Generalized LC-MS and LC-MS/MS Protocol.

8.10 Conclusions.

Acknowledgments.

References.

9. Characterization of Surface-Modifi ed Fibers (Robert D. Blackledge and Kurt Gaenzle).

9.1 Fibers as Associative Evidence.

9.2 Surface-Modifi ed Fibers.

9.3 Preliminary Examinations.

9.3.1 Infrared Spectra and Properties Measured by Polarized Light Microscopy.

9.3.2 Infrared Mapping with an FTIR Microscope.

9.3.3 Raman Mapping.

9.3.4 AATCC Test Method 118-2002.

9.3.5 A Simple Example.

9.4 Distinguishing Tests.

9.4.1 Scanning Electron Microscopy/Energy Dispersive Spectroscopy.

9.4.2 Gas Chromatography/Mass Spectrometry.

9.4.3 Pyrolysis Gas Chromatography/Mass Spectrometry.

Acknowledgments.

References.

10. Characterization of Smokeless Powders (Wayne Moorehead).

10.1 Introduction.

10.2 Purpose of Analysis.

10.2.1 Identifi cation of Smokeless Powder.

10.2.2 Determining Brand.

10.3 Brief History of Smokeless Powder.

10.4 Characterization Toward Smokeless Powder Identification.

10.5 Characterization Toward Brand Identification.

10.5.1 Characterization by Morphology.

10.5.2 Micromorphology.

10.5.3 Other Characteristics.

10.6 Micrometry.

10.7 Mass.

10.8 FTIR Spectroscopy.

10.8.1 Transmission Micro-FTIR.

10.8.2 ATR-FTIR.

10.9 Chromatography with Mass Spectrometry.

10.9.1 Gas Chromatography.

10.9.2 Liquid Chromatography.

10.10 Conclusion.

References.

11. Glass Cuts (Helen R. Griffin).

11.1 A Homicide.

11.2 A Robbery.

11.3 A Hit and Run.

11.4 Cutting Versus Tearing.

11.5 Slash Cuts Made by Glass.

11.5.1 Associated Glass.

11.5.2 Fabric Type.

11.5.3 Blade Characteristics.

11.6 Conclusion.

Acknowledgments.

References.

Additional Sources.

12. Forensic Examination of Pressure Sensitive Tape (Jenny M. Smith).

12.1 Introduction.

12.2 Product Variability.

12.3 Tape Construction.

12.3.1 Tape Backings.

12.3.2 Adhesive Formulations.

12.3.3 Common Reinforcement Fabrics.

12.4 Duct Tape.

12.5 Electrical Tape.

12.6 Polypropylene Packaging Tape.

12.6.1 Oriented Films.

12.6.2 Polarized Light Microscopy Examinations of Packing Tapes.

12.6.3 Is It MOPP or BOPP?

12.6.4 Thickness.

12.6.5 Degree of Offset from the Machine Edge.

12.7 Strapping/Filament Tapes.

12.8 Masking Tape.

12.9 Initial Handling.

12.9.1 Sharing Evidence with Other Sections.

12.9.2 Untangling Tape and Recovering Trace Evidence.

12.10 Methods.

12.10.1 Physical End Matching.

12.10.2 Physical Characteristics.

12.10.3 Separation of Backing, Reinforcement, and Adhesive.

12.10.4 FTIR Analysis.

12.10.5 Elemental Analysis.

12.10.6 Polarized Light Microscopy.

12.10.7 Pyrolysis GC/MS.

12.10.8 Sourcing Tape Products to a Manufacturer.

12.11 Case Example.

Acknowledgments.

References.

Additional Sources.

13. Discrimination of Forensic Analytical Chemical Data Using Multivariate Statistics (Stephen L. Morgan and Edward G. Bartick).

13.1 Patterns in Data.

13.2 Experimental Design and Preprocessing.

13.3 Dimensionality Reduction by Principal Component Analysis for Visualizing Multivariate Data.

13.4 Visualizing Group Differences by Linear Discriminant Analysis.

13.5 Group Separation, Classifi cation Accuracy, and Outlier Detection.

13.6 Selected Applications.

13.7 Conclusion.

Acknowledgments.

References.

14. The Color Determination of Optically Variable Flake Pigments (Michael R. Nofi).

14.1 Introduction.

14.2 OVP: Form, Characteristics, and Function.

14.3 Color Measurement.

14.4 Color Blending.

14.5 Additive Color Theory.

14.6 Methods of Formulating OVP.

14.7 Blending of Pigments.

14.8 Microspectrophotometry.

14.9 Measurement Geometry.

14.10 Switching Objective Magnifi cations.

14.11 Determining Sample Size.

14.12 Measurement Uncertainty.

14.13 Sample Preparation and Measurement.

14.14 Spectral Profi ling.

14.15 Statistical Methods of Evaluation.

14.16 Challenges for the Future.

14.17 Other forensic Methods.

Acknowledgments.

References.

Additional Sources.

15. Forensic Science Applications of Stable Isotope Ratio Analysis (James R. Ehleringer, Thure E. Cerling, and Jason B. West).

15.1 What Are Stable Isotopes?

15.2 What Are the Units for Expressing the Abundance of Stable Isotopes?

15.3 What Is the Basis for Variations in Stable Isotope Abundances?

15.4 What Instrumentation Is Needed for High-Precision Stable Isotope Measurements?

15.5 How Can Stable Isotope Analyses Assist Forensics Cases?

15.6 Stable Isotope Abundances in Forensic Evidence.

15.6.1 Food Products, Food Authenticity, and Adulteration.

15.6.2 Doping and Drugs of Abuse.

15.6.3 Sourcing of Humans, Animals, and Animal Products.

15.6.4 Humans: Bones, Hair, and Teeth.

15.6.5 Stable Isotope Abundances of Manufactured  Items.

References.

Index.