Forensic Chemistry

Jay Siegel, Emeritus Professor of Forensic Science, Michigan State University Jay Siegel is Director of the Forensic and Investigative Sciences Program at Indiana University Purdue University, Indianapolis and Chair of the Department of Chemistry and Chemical Biology. He holds a Ph.D. in Analytical Chemistry from George Washington University. He worked for 3 years at the Virginia Bureau of Forensic Sciences, analyzing drugs, fire residues and trace evidence. From 1980 to 2004 he was professor of forensic chemistry and Director of the forensic science program at Michigan State University in the School of Criminal Justice. He is Editor in Chief of the Encyclopedia of Forensic Sciences, author of Forensic Science: A Beginner's Guide and Fundamentals of Forensic Science and has over 30 publications in forensic science journals. Dr. Siegel was awarded the 2005 Paul Kirk Award for lifetime achievement in forensic science. In February 2009, he was named Distinguished Fellow by the American Academy of Forensic Sciences. In April 2009 he was named the Distinguished Alumni Scholar Award by his alma mater, George Washington University.

About the editor, xii

Contributors, xiii

Series preface, xv

Preface, xvi

1 Drugs of abuse, 1
Niamh Nic Daéid

1.1 Introduction, 1

1.2 Law and legislation, 2

1.3 Sampling, 4

1.3.1 Random sampling and representative sampling, 6

1.3.2 Arbitrary sampling, 7

1.3.3 Statistical sampling methods, 8

1.4 Specific drug types, 9

1.4.1 Cannabis, 9

1.4.2 Heroin, 14

1.4.3 Cocaine, 22

1.4.4 Amphetamine]type stimulants, 27

1.4.5 New psychoactive substances, 33

1.5 Conclusions, 36

Acknowledgements, 36

References, 36

2 Textiles, 40
Max Houck

2.1 Introduction, 40

2.2 A science of reconstruction, 40

2.2.1 Classification, 41

2.2.2 Comparison, 42

2.2.3 Transfer and persistence, 43

2.3 Textiles, 43

2.3.1 Information, 44

2.3.2 Morphology, 45

2.4 Natural fibers, 48

2.4.1 Animal fibers, 48

2.4.2 Plant fibers, 51

2.5 Manufactured fibers, 52

2.6 Yarns and fabrics, 55

2.6.1 Fabric construction, 56

2.6.2 Finishes, 59

2.7 Fiber types, 59

2.7.1 Acetate, 59

2.7.2 Acrylic, 59

2.7.3 Aramids, 60

2.7.4 Modacrylic, 60

2.7.5 Nylon, 61

2.7.6 Olefins (polypropylene and polyethylene), 61

2.7.7 Polyester, 62

2.7.8 Rayon, 62

2.7.9 Spandex, 65

2.7.10 Triacetate, 66

2.7.11 Bicomponent fibers, 66

2.8 Chemistry, 67

2.8.1 General analysis, 67

2.8.2 Instrumental analysis, 68

2.8.3 Color, 69

2.8.4 Raman spectroscopy, 70

2.8.5 Interpretation, 71

2.9 The future, 72

References, 72

3 Paint and coatings examination, 75
Paul Kirkbride

3.1 Introduction, 75

3.2 Paint chemistry, 76

3.2.1 Binders, 76

3.2.2 Dyes and pigments, 86

3.2.3 Additives, 89

3.3 Automotive paint application, 91

3.4 Forensic examination of paint, 92

3.4.1 General considerations, 92

3.4.2 Microscopy, 95

3.4.3 Vibrational spectrometry, 96

3.4.4 SEM]EDX and XRF, 106

3.4.5 Pyrolytic techniques, 111

3.4.6 Color analysis, 116

3.5 Paint evidence evaluation and expert opinion, 120

References, 128

Contents vii

4 Forensic fire debris analysis, 135
Reta Newman

4.1 Introduction, 135

4.2 Process overview, 135

4.3 Sample collection, 136

4.4 Ignitable liquid classification, 137

4.5 Petroleum]based ignitable liquids, 144

4.6 Non]petroleum]based ignitable liquids, 160

4.7 Sample preparation, 161

4.8 Sample analysis and data interpretation, 166

4.9 Summary, 172

References, 173

5 Explosives, 175
John Goodpaster

5.1 The nature of an explosion, 175

5.1.1 Types of explosions, 175

5.1.2 Explosive effects, 176

5.2 Physical and chemical properties of explosives, 180

5.2.1 Low explosives, 181

5.2.2 High explosives, 186

5.3 Protocols for the forensic examination of explosives and explosive devices, 192

5.3.1 Recognition of evidence, 192

5.3.2 Portable technology and on]scene analysis, 193

5.3.3 In the laboratory, 194

5.4 Chemical analysis of explosives, 200

5.4.1 Consensus standards (TWGFEX), 201

5.4.2 Chemical tests, 203

5.4.3 X]ray techniques, 204

5.4.4 Spectroscopy, 207

5.4.5 Separations, 212

5.4.6 Gas chromatography, 213

5.4.7 Mass spectrometry, 215

5.4.8 Provenance and attribution determinations, 219

5.5 Ongoing research, 221

Acknowledgements, 222

References, 222

Further reading, 226

6 Analysis of glass evidence, 228
Jose Almirall and Tatiana Trejos

6.1 Introduction to glass examinations and comparisons, 228

6.2 Glass, the material, 231

6.2.1 Physical and chemical properties, 231

6.2.2 Manufacturing, 233

6.2.3 Fractures and their significance, 236

6.2.4 Forensic considerations: Transfer and persistence of glass, 238

6.3 A brief history of glass examinations, 241

6.4 Glass examinations and comparison, standard laboratory practices, 242

6.4.1 Physical measurements, 243

6.4.2 Optical measurements, 244

6.4.3 Chemical measurements: elemental analysis, 247

6.5 Interpretation of glass evidence examinations and comparisons, 256

6.5.1 Defining the match criteria, 256

6.5.2 Descriptive statistics, 256

6.5.3 Match criteria for refractive index measurements, 257

6.5.4 Informing power of analytical methods, forming the opinion, 260

6.5.5 Report writing and testimony, 262

6.6 Case examples, 263

6.6.1 Case 1: Hit]and]run case, 263

6.6.2 Case 2: Multiple transfer of glass in breaking]and]entry case, 264

6.7 Conclusions, 265

References, 266

7 The forensic comparison of soil and geologic microtraces, 273
Richard E. Bisbing

7.1 Soil and geologic microtraces as trace evidence, 273

7.2 Comparison process, 274

7.3 Developing expertise, 278

7.4 Genesis of soil, 279

7.5 Genesis of geologic microtraces, 284

7.6 Collecting questioned samples of unknown origin, 287

7.7 Collecting soil samples of known origin, 288

7.8 Initial comparisons, 290

7.9 Color comparison, 290

7.10 Texture comparison, 293

7.11 Mineral comparison, 297

7.12 Modal analysis, 301

7.13 Automated instrumental modal analysis, 308

7.14 Ecological constituents, 310

7.15 Anthropogenic constituents, 312

7.16 Reporting comparison results, 312

7.17 Future directions and research, 314

Acknowledgments, 314

References, 315

Further reading, 316

8 Chemical analysis for the scientific examination of questioned documents, 318
Gerald M. LaPorte

8.1 Static approach, 320

8.2 Dynamic approach, 324

8.3 Ink composition, 324

8.4 Examinations, 328

8.4.1 Physical examinations, 329

8.4.2 Optical examinations, 332

8.4.3 Chemical examinations, 333

8.4.4 Paper examinations, 339

8.5 Questioned documents, crime scenes and evidential considerations, 342

8.5.1 How was the questioned document produced?, 342

8.5.2 What evidence can be used to associate a questioned document with the crime scene and/or victim?, 343

8.5.3 Are there other forensic examinations that can be performed?, 345

8.5.4 Demonstrating that a suspect altered a document, 346

8.6 Interpreting results and rendering conclusions, 347

References, 350

9 Chemical methods for the detection of latent fingermarks, 354
Amanda A. Frick, Patrick Fritz, and Simon W. Lewis

9.1 Introduction, 354

9.2 Sources of latent fingermark residue, 355

9.2.1 Aqueous components, 356

9.2.2 Lipid components, 357

9.2.3 Sources of compositional variation, 359

9.3 Chemical processing of latent fingermarks, 361

9.3.1 Amino acid sensitive reagents, 361

9.3.2 Reagents based on colloidal metals, 370

9.3.3 Lipid]sensitive reagents, 377

9.3.4 Other techniques, 383

9.4 Experimental considerations for latent fingermark chemistry research, 384

9.5 Conclusions and future directions, 387

Acknowledgements, 388

References, 388

Further reading, 398

10 Chemical methods in firearms analysis, 400
Walter F. Rowe

10.1 Introduction, 400

10.2 Basic firearms examination, 400

10.2.1 Cleaning bullets and cartridges, 402

10.2.2 Analysis of bullet lead, 404

10.2.3 Serial number restoration, 406

10.3 Shooting incident reconstruction, 408

10.3.1 Muzzle]to]target determinations, 411

10.3.2 Firearm primers, 416

10.3.3 Collection of gunshot residue, 425

10.4 Conclusion, 433

References, 433

11 Forensic microscopy, 439
Christopher S. Palenik

11.1 The microscope as a tool, 439

11.2 Motivation, 440

11.2.1 Intimidation, 442

11.2.2 Limitations, 442

11.3 Scale, 442

11.3.1 Scale and magnification, 443

11.3.2 Noting scale, 443

11.3.3 Analytical volume and limits of detection, 443

11.4 Finding, 445

11.4.1 Spatial resolution, 445

11.4.2 Recovery resolution, 447

11.4.3 Stereomicroscope, 447

11.5 Preparing, 448

11.5.1 Preservation and documentation, 448

11.5.2 Isolation, 450

11.5.3 Mounting, 451

11.6 Looking, 455

11.6.1 Light microscopy, 456

11.6.2 Scanning electron microscopy, 457

11.7 Analyzing, 458

11.7.1 Polarized light microscopy, 458

11.7.2 Energy dispersive X]ray spectroscopy, 462

11.7.3 FTIR and Raman spectroscopy, 464

11.7.4 Other methods, 465

11.8 Thinking, 465

11.9 Thanking, 467

References, 467

12 Chemometrics, 469
Ruth Smith

12.1 Introduction, 469

12.2 Chromatograms and spectra as multivariate data, 470

12.3 Data preprocessing, 470

12.3.1 Baseline correction, 471

12.3.2 Smoothing, 473

12.3.3 Retention]time alignment, 473

12.3.4 Normalization and scaling, 475

12.4 Unsupervised pattern recognition, 477

12.4.1 Hierarchical cluster analysis, 478

12.4.2 Principal components analysis, 480

12.5 Supervised pattern recognition procedures, 485

12.5.1 k]Nearest neighbors, 486

12.5.2 Discriminant analysis, 487

12.5.3 Soft independent modeling of class analogy, 492

12.5.4 Model validation, 493

12.6 Applications of chemometric procedures in forensic science, 494

12.6.1 Fire debris and explosives, 495

12.6.2 Controlled substances and counterfeit medicines, 496

12.6.3 Trace evidence, 497

12.6.4 Impression evidence, 499

12.7 Conclusions, 499

Acknowledgements, 500

References, 500

Index, 504