Description
Book SynopsisForensic Ballistics in Court: Interpretation and Presentation of Firearms Evidence is an accessible introduction to firearms and ballistics evidence and how this is analysed and presented as evidence in a court of law.
The book approaches the subject in terms of the realities of case work, opening with a clear and illustrated explanation of the correct nomenclature for various weapon types and their parts. Ammunition is also extensively covered, again with annotated illustrations. Basic external and terminal ballistics, wounding capabilities are likewise covered to give an overview of the subject. A key aspect of the book covers the theory and philosophy behind striation matches and the associated statistics, how positive matches should be peer reviewed and the importance accreditation has on this subject.
Gunshot residue formation and identification and the various methods used in its analysis are reviewed in depth. This includes a critical examination of the p
Table of Contents
About the Author xiii
Introduction xv
About the companion website xix
1.0 Firearms History 1
1.0.1 Introduction 1
1.0.2 The flintlock 1
1.0.3 The percussion system 3
1.0.4 The pinfire system 3
1.0.5 The rimfire system 4
1.0.6 The Dreyse needle fire system 4
1.0.7 The centre fire system 5
1.0.8 The revolver 5
1.0.9 The self-loading pistol 6
Further reading 8
2.0 Weapon Types and Their Operation 9
2.0.1 Introduction 9
2.0.2 Handguns 9
2.0.3 Rifles 13
2.0.4 Shotguns 14
2.0.5 Combination weapons 15
2.0.6 Sub-machine guns 15
2.0.7 Assault rifles 16
2.0.8 Machine guns and heavy machine guns 16
2.0.9 Muzzle attachments 16
2.0.10 Important parts of a weapons mechanism 19
2.0.11 Bent and sear 20
2.0.12 Other important parts of a revolver mechanism 22
2.0.13 Hand and ratchet 23
Further reading 24
2.1 Gas and Air Powered Weapons 25
2.1.1 Introduction 25
2.1.2 Weapon types 25
2.1.3 Ammunition 28
2.1.4 Considerations 30
Further reading 31
2.2 Rifling Types and Their Identification 33
2.2.1 Introduction 33
2.2.2 Basics 34
2.2.3 Class characteristics 37
2.2.4 General introduction to rifling 38
Additional reading 42
2.3 Home-made, Improvised and Converted Firearms 43
2.3.1 Introduction 43
2.3.2 Improvised firearms 43
2.3.3 Converting air weapons 44
2.3.4 Home-made and converted toys and replica weapons 45
2.3.5 Home-made ammunition 48
Further reading 50
2.4 Antique Weapons 51
2.4.1 Introduction 51
2.4.2 Background 51
2.4.3 Defining ‘antique’ 52
3.0 Proof Marks 55
3.0.1 Introduction 55
3.0.2 Proof marks 55
3.0.3 Types of proof 56
3.0.4 Proof marks and the examiner 56
3.0.5 Examples of proof marks 56
Further reading 61
4.0 A Brief History of Ammunition 63
4.0.1 Introduction 63
4.0.2 Basics 63
Further reading 66
4.1 Ammunition Components 67
4.1.1 Introduction 67
4.1.2 Basics 67
4.1.3 Ammunition types 68
4.1.4 Primer cap types 69
4.1.5 Cartridge cases 70
4.1.6 Shotgun ammunition 73
Further reading 79
4.2 Bullet Types 81
4.2.1 Introduction 81
4.2.2 Basics 81
4.2.3 Bullet materials 81
4.2.4 Other bullet types 83
4.2.5 Bullet nose configuration 83
4.2.6 Bullet base configuration 85
4.2.7 Bullet lubrication 85
Further reading 86
4.3 Headstamps and Other Identifying Features on Ammunition 87
4.3.1 Introduction 87
4.3.2 Basics 88
4.3.3 Clandestine ammunition 89
4.3.4 Colour coding of ammunition 90
Further reading 91
4.4 Non-toxic and Frangible Bullets 93
4.4.1 Introduction 93
4.4.2 Elimination of lead in ammunition 93
4.4.3 Materials used in non-toxic ammunition 94
4.4.4 The current situation 94
Further reading 96
4.5 Non-toxic Shot 97
4.5.1 Introduction 97
4.5.2 Materials used in non-toxic shotgun ammunition 97
Suggested further reading 100
4.6 A Brief History of Propellants 101
4.6.1 Introduction 101
4.6.2 Basics 101
4.6.3 Black powder 102
4.6.4 Nitro propellants 104
4.6.5 Dating of ammunition 107
4.6.6 Reduced loads for target shooting 107
Further reading 108
4.7 Priming Compounds 109
4.7.1 Introduction 109
4.7.2 Basics 110
4.7.3 A short history of priming compounds 110
4.7.4 Manufacture 113
4.7.5 Accidental discharge of primers 113
Further reading 114
5.0 An Introduction to Ballistics 115
5.0.1 Introduction 115
5.0.2 Basics 115
5.0.3 Background 115
Further reading 116
5.1 Internal Ballistics 117
5.1.1 Introduction 117
5.1.2 Basics 117
5.1.3 Recoil 118
5.1.4 Barrel pressure 120
Further reading 121
5.2 External Ballistics 123
5.2.1 Introduction 123
5.2.2 Basics 124
5.2.3 Maximum range of missiles 126
5.2.4 Maximum altitude that a bullet will attain 130
5.2.5 Terminal velocity 131
5.2.6 Use of sight to compensate for bullet drop 132
5.2.7 Other influencing factors 132
5.2.8 Muzzle energy 134
5.2.9 Momentum 135
Further reading 135
5.3 Terminal Ballistics 137
5.3.1 Introduction 137
5.3.2 Basics 137
5.3.3 General wound ballistic concepts 139
5.3.4 Other factors influencing the wounding capabilities of a missile 144
5.3.5 Bullet performance and ‘wounding capabilities’ 145
5.3.6 Relative stopping power (RSP) 147
5.3.7 Bullet resistant vests (BRV) 149
Further reading 152
6.0 A Brief History of Forensic Firearms Identification 153
6.0.1 Introduction 153
6.0.2 Early cases involving bullet identification 154
6.0.3 Use of photomicrographs 154
6.0.4 Identification of weapon from breech face markings 155
6.0.5 Early use of comparison microscope 155
6.0.6 Introduction of the binocular comparison microscope 156
6.0.7 Improvements in illumination 157
6.0.8 Photography of stria 157
6.0.9 Modern technology for stria comparison 157
Suggested further reading 160
7.0 Basic Concepts of Striation Matching 161
7.0.1 Introduction 161
7.0.2 Basics 162
7.0.3 Identification of weapon type 164
7.0.4 Individual characteristics on cartridge cases 165
7.0.5 Formation of stria 166
7.0.6 Problematical areas 167
Further reading 172
7.1 Basic Concepts in Comparison Microscopy 173
7.1.1 Introduction 173
7.1.2 Basic methodology and background to stria comparisons 174
7.1.3 Lighting used for comparison microscopy 175
7.1.4 The concept of consecutive matching stria 177
7.1.5 Obtaining control samples 177
7.1.6 Manufacturing marks on ammunition 178
7.1.7 Recovery methods for fired bullets 178
7.1.8 Conclusion 180
Further reading 181
7.2 The Concept of Consecutive Matching Stria 183
7.2.1 Introduction 183
7.2.2 Basics 183
7.2.3 Arguments for and against the concept of stria comparisons 186
Further reading 187
7.3 A Statistical Model to Illustrate the Concept of Individuality in Striation Matches 189
7.3.1 Introduction 189
7.3.2 Basics 189
7.3.3 Stria individuality 190
7.3.4 Philosophy 191
References 193
8.0 Accidental Discharge 195
8.0.1 Introduction 195
8.0.2 Basics 197
8.0.3 Trigger mechanisms 197
8.0.4 Reasons for an accidental discharge 198
8.0.5 Negligent discharges 203
Further reading 204
9.0 Identification of Calibre from the Bullet Entry Hole 205
9.0.1 Introduction 205
9.0.2 Basics 206
9.0.3 Determination of bullet type 207
Further reading 208
10.0 Ricochet Analysis 209
10.0.1 Introduction 209
10.0.2 Basics 209
10.0.3 Variables influencing the liability of a missile to ricochet 210
Further reading 213
11.0 Bullet Penetration and Trajectory through Glass 215
11.0.1 Introduction 215
11.0.2 Glass types and glass substitutes 215
11.0.3 Deviation of missile after penetrating glass 217
11.0.4 Penetration of normal window glass 217
11.0.5 Penetration of laminated and bullet-resistant glass 218
11.0.6 Penetration of tempered or toughened glass 219
11.0.7 Determination of bullet type from the entry hole 220
11.0.8 Deflection of bullet by glass 221
Further reading and references 223
12.0 Range of Firing Estimations and Bullet Hole Examinations 225
12.0.1 Introduction 225
12.0.2 Basics 225
12.0.3 Range of firing estimations for pistols and rifles 227
12.0.4 Extended range of fire estimations 230
12.0.5 Range of firing estimations on badly decomposed bodies 231
12.0.6 Bullet wipe marks 231
12.1 Chemical Tests for Range of Fire Estimations and Bullet Entry/Exit Hole Identification 235
12.1.1 Introduction 235
12.1.2 Chemical tests for range of firing estimations 235
12.1.3 Range of firing estimations on heavily bloodstained garments 237
12.1.4 Range of firing estimations for non-toxic non-lead primers 238
Further reading 239
12.2 Range of Fire Estimations for Shotguns 241
12.2.1 Introduction 241
12.2.2 Basics 242
12.2.3 Shotgun cartridges fired in revolvers 246
Suggested further reading 247
13.0 The Use of X-ray Photography for Projectile Identification 249
13.0.1 Introduction 249
13.0.2 Estimation of calibre from X-ray photographs 250
Further reading 254
14.0 Gunshot Residue Examination 255
14.0.1 Introduction 255
14.0.2 Basics 256
14.0.3 Identification of GSR Particles 257
14.0.4 The use of the scanning electron microscope (SEM) with energy dispersive X-Ray analysis (EDX) for the detection and analysis of GSR particles 259
14.0.5 Sample collection 260
14.0.6 GSR retention 263
14.0.7 Interpretation of results 264
14.0.8 Identification of type of ammunition and country or origin from GSR composition 265
14.0.9 Environmental contaminants 267
14.0.10 Extending the period over which GSR particles can be recovered 269
14.0.11 General considerations to be made when examining GSR analysis results 272
14.0.12 Discussion 274
References 275
15.0 Gun Handling Tests 277
15.0.1 Introduction 277
15.0.2 History 278
15.0.3 Methodology for the use of Ferrozine 279
Further reading 283
16.0 Laser-etched Serial Numbers and Bar Codes 285
16.0.1 Introduction 285
16.0.2 Laser-etched serial numbers 285
16.0.3 Bar codes 286
16.0.4 Conclusion 287
Further reading 287
17.0 Classification of Firearms-related Death 289
17.0.1 Introduction 289
17.0.2 Basics 289
17.0.3 Multiple shot suicides 290
References and further reading 293
18.0 Practical Considerations in a Firearms Case from a Legal Point of View 295
18.0.1 Introduction 295
18.0.2 Key questions 296
18.0.3 Legal challenges to forensic firearms evidence in the USA 298
18.0.4 Conclusion 300
Further reading and references 300
19.0 Qualifying the Expert and Cross-examination Questions 301
19.0.1 Definition 301
19.0.2 Introduction 301
19.0.3 Qualifying the expert 302
19.0.4 General background questions 303
19.0.5 Comparison microscopy 303
19.0.6 Gunshot residue 306
19.0.7 Ferrozine test 308
Further reading 308
20.0 Chain of Custody 309
20.0.1 Introduction 309
20.0.2 Basics 309
20.0.3 Process 310
20.0.4 In court 310
Further reading 311
Appendix 1 Standard of Review: ‘Daubert Trilogy’ 313
Appendix 2 Commercial and General Abbreviations for Bullet Configurations 317
Appendix 3 Some of the More Common Trade Names 323
Appendix 4 Important dates in the History of Firearms from 1247 335
Appendix 5 Dates for the Introduction of Various Cartridges by Calibre 341
Appendix 6 Some Trademarks Found on Guns 345
Appendix 7 General Firearms Values Conversion Table 349
Appendix 8 Hearing Loss 351
Appendix 9 A List of Handgun Cartridges 355
Appendix 10 A List of Rifle Cartridges 357
Appendix 11 Air Weapon Legislation 361
Index 367
