Introduction to Forensics by Piyush B. Thakur
- 1. Piyush B. Thakur (Pursuing PhD in Forensic Science) Jr. Scientist
- 2. …the application of science to those criminal and civil laws that are enforced by police agencies in a criminal justice system.
- 3. Applied Science Often called “criminalistics”
- 4. Chemistry Biology Physics Geology Places physical evidence into a professional discipline. to civil and criminal law }
- 6. Popularized physical detection methods in a crime scene Developed the character Sherlock Holmes
- 7. 1887 published first novel, A Study in Scarlet "I've found it! I've found it," he shouted to my companion, running towards us with a test-tube in his hand. "I have found a re-agent which is precipitated by haemoglobin, and by nothing else . . . . Why, man, it is the most practical medico-legal discovery for years. Don't you see that it gives us an infallible test for blood stains? . . . . The old guaiacum test was very clumsy and uncertain. So is the microscopic examination for blood corpuscles. The latter is valueless if the stains are a few hours old. Now, this appears to act as well whether the blood is old or new. Had this test been invented, there are hundreds of men now walking the earth who would long ago have paid the penalty of their crimes. . . . Criminal cases are continually hinging upon that one point. A man is suspected of a crime months perhaps after it has been committed. His linen or clothes are examined and brownish stains discovered upon them. Are they blood stains, or mud stains, or rust stains, or fruit stains, or what are they? That is a question which has puzzled many an expert, and why? Because there was no reliable test. Now we have the Sherlock Holmes's test, and there will no longer be any difficulty." → had a considerable influence on popularizing scientific crime-detection methods
- 8. Father of Forensic Toxicology 1814 - Treatise on detection of poisons & their effects on animals.
- 9. Father of Criminal Detection Devised the first scientific system of personal identification, using body measurements known as anthropometry in 1879.
- 10. Conducted the first definitive study of fingerprints and their classification. 1892 – Treatise entitled Finger Prints
- 11. Devised a simple procedure for determining the blood type (A,B,O,AB) of a dried bloodstain
- 12. Used a comparison microscope to determine if a bullet was fired from a specific gun Published study of “tool marks” on bullets
- 13. Developed fundamental principles of document examination 1910 – Treatise Questioned Documents Was responsible for the acceptance of documents as scientific evidence by the courts
- 14. Demonstrated how the principles developed by Hans Gross could be incorporated into a workable crime lab. Locard's exchange principle states that once contact is made between two surfaces a transfer of material(s) will occur.
- 16. Since the 1960's the number of crime labs increased due to the courts demanding secure scientifically evaluated evidence. More crime More drug related crime Greater need for physical evidence Use of DNA profiling (1990’s)
- 18. Physical Science Unit: Applies the principles and techniques of Chemistry Physics Geology to the identification and comparison of crime-scene evidence Biology Unit: Identifies dried bloodstains and body fluids Compares hairs and fibers Identifes and compares botanical materials such as wood and plants Performs DNA analysis
- 19. Firearms Unit: examines Firearms Discharged bullets Cartridge cases Shotgun shells Ammunition of all types Document Examination Unit: Analyzes handwriting, paper and printers of documents Photography Unit: Examines and records physical evidence at the crime scene and at suspects' locations
- 20. Toxicology Unit: Examines body fluids and organs in order to determine the presence and identification of drugs and poisons Latent Fingerprint Unit: Processes and examines evidence for latent fingerprints i.e. those found on surfaces Polygraph Unit: Uses lie detectors, an essential tool of the crime investigator rather than the forensic scientist
- 21. Voiceprint Analysis Unit: Involved in cases of telephone threats or tape- recorded messages Investigators may be able to connect a voice to a particular suspect Evidence-Collection Unit: Incorporates evidence collection into a total forensic science service
- 22. Analysis of Physical Evidence The forensic scientist must be skilled in applying the principles and techniques of the physical and natural sciences in order to identify the many types of evidence that may be recovered during crime investigations. Expert witness An expert witness possesses a particular skill or has knowledge in a trade or profession that will aid the court in determining the truth.
- 23. Specially trained evidence collection technicians □ Training in Proper Recognition, Collection, and Preservation of Evidence is required so that the forensic pathologist, as the medical examiner or coroner, can determine the cause of death via an autopsy.
- 24. Death can be classified into five different categories: natural death, homicide, suicide, accident or undetermined manner of death. Forensic Pathology The cause of death can often be determined by performing an autopsy
- 25. Forensic Pathology – continued After a human body expires there are several stages of death ▪ Rigor Mortis ▪ immediately following death, the muscles relax and then become rigid, shortening of the muscles. ▪ Livor Mortis ▪ when the human heart stops pumping, due to the blood begins to settle in the parts of the body closest to the ground due to gravity. The skin will appear dark blue or purple in these lower areas close to the ground. ▪ Algor Mortis ▪ the process in which the body temperature continually cools after death until it reaches room temperature, enabling the medical examiner to establish the general time of death.
- 26. Forensic Anthropology: Primarily involves the identification and examination of skeletal remains, in order to determine if the remains are human or another type of animal. If human, ethnicity, sex, approximate age, and manner of death can often be determined by an anthropologist.
- 27. Forensic Entomology The study of insects and their developmental stages Can help to determine the time of death by knowing when those stages normally appear in the insect's life cycle
- 28. . Forensic Psychiatry The study of human behavior and legal proceedings in both civil and criminal cases In civil and criminal cases, competency often needs to be determined In criminal trials, the evaluation of behavior disorders is often required in order to establish the psychological profile of a suspect
- 29. Forensic Odontology An odontologist can match bite marks to a suspect's teeth, or match a victim to his dental x- rays Results in an identification of an unknown individual Forensic Engineering Used to analyze construction accidents, and the causes and origins of fires or explosions
- 30. Can include organic and inorganic analytical techniques Organic analysis of unknown substances ▪ Includes analytical techniques such as Chromatography, UV- visible and infrared Spectrophotometry and Mass Spectrometry. Inorganic analysis ▪ Includes techniques such as the emission spectrum of elements, Atomic Absorption Spectrophotometry, Neutron Activation Analysis, and X-Ray Diffraction Analysis.