intro to forensic science_hand-out

FORENSIC SCIENCE

PSUPT JAIME RODRIGO L LEAL, MD

A View on Evidence

Evidence

Direct Circumstantial

Physical Biological

Common Types of Physical EvidenceDrug and toxic substance

Resins, plastics Fingerprints

Paints Explosive residues

Hair

Gun shot residues (GSR)

Serial numbers Tissues

Firearms and ammunition

Documents Pollen

Impressions Fibers Wood material

Petroleum products Soil Feathers

Alcohols (esp. ethanol)

Glass Bones

Rubber material Blood and other body fluids

Tool marks

Wherever he steps, whatever he touches, whatever he leaves even

unconsciously, will serve as a silent witness against him. Not only his

fingerprints or footprints, but his hair, fibers from his clothes, the glass he

breaks, the tool marks he leaves, the paint he scratches, the blood or semen he deposits or collects – all of these and

more bear mute witness against him.- Dr. Edmond Locard

TRACE EVIDENCE:LOCARD’S

TRANSFERENCE PRINCIPLE

“When any two objects come in contact there is always a transfer of material from each object on to the other.”

TRACE EVIDENCE:LOCARD’S

TRANSFERENCE PRINCIPLE

“Any person committing a crime leaves something at the crime scene that was not there before and carries away traces that were associated with him when he or she arrived.”

Transference Theory

“EVERY CONTACT LEAVES A TRACE.”

- Dr. Edmond Locard

What is Forensic Science?

Definition

Forensic science

- often shortened to forensics - the application of a broad

spectrum of sciences to answer questions of interest to a legal system.

- the word forensic comes from the Latin adjective forensis, meaning "of or before the forum.”

Forensic Science Defined

Forensic Science is any science used for the purposes of the law, and therefore provides impartial scientific evidence for use in the courts of law.

Forensic Science is a multidisciplinary subject, drawing principally from chemistry and biology, but also physics, geology, psychology, social science, etc.

What is Forensic Investigation?

Forensic Investigation Defined

Forensic Investigation is a combination of forensic

science, law and criminal investigation and can be

described as a problem-solving activity. 

Interest of Forensic Investigation

Observe physical evidence

Determine identity

Determine origin

Philosophy of Forensics

The key to criminalistics is the ability to think clearly when faced with the daunting confusion of the average crime scene.

One must rely on experience, intuition and abductive reasoning (testing a likely scenario against the facts)

History

The dawn of forensic science took place in the civilization of ancient China (T’ang Dynasty).

Ti Jen-Chieh used both logic and forensic evidence to solve crimes in 7th century AD. He utilized a team of investigators, studied the crime scene, examined evidence, and interviewed witnesses and suspects.

Forensic science owes much to the age of scientific discovery in the 16th, 17th, and 18th centuries. Jansen – Microscope in 1950 Schultze – Photographic film in 1724 Niepce and Daguerre – First photograph in 1826

People Behind Forensics

St. Thomas, the Doubter The Patron Saint of Forensic Science

Sir Conan Doyle Sci-fi author in late 1800s and has popularized scientific crime-detection methods through his fictional character “Sherlock Holmes”

Matheiu Orfila (1787-1853) The father of Toxicology and wrote about the detection of poisons and their effects on animals

People Behind Forensics

Alphonse Bertillon (1853-1914) The father of Anthropometry and developed the system to distinguish one individual person from another based on certain body measurements

Francis Galton (1822-1911) The father of Fingerprinting and has developed fingerprinting as a way to uniquely identify individuals

Leone Lattes (1887-1954) The father of Bloodstain Identification and developed a procedure for determining the blood type (A, B, AB or O) of a dried blood stain

People Behind Forensics

Albert Osborne (1858-1946) The father of Document Examination where his work led to the acceptance of documents as scientific evidence by the courts

J. Edgar Hoover The father of the FBI during the 1930s where he organized a national laboratory to offer forensic services to all law enforcement agencies in the United States

Edmond Locard (1877-1966) The father of Crime Lab where he started the 1st crime lab

in an attic of a police station. He founded the Institute of Criminalistics in France and developed the Locard’s Exchange Principle

Scientific Methods in Forensics Observe problem or questioned evidence and collected data

Make hypothesis or possible solution to the problem based on the observations, given a directed work plan

Examine, test and analyze to support or refute hypothesis

Use deductive reasoning to make a determination as to the significance of the evidence

Evaluate and verify all evidence and determine a conclusion

Forensic Science Field in Investigation

Physics Chemistry Biology DNA Analysis Firearms Identification / Ballistics Toxicology Document Examination and Analysis Photography Dactyloscopy Medicine / Pathology Dentistry Crime Scene Investigation Anthropology Entomology Computer Forensics

Forensic Specialties

Crime Scene Investigation deals with the techniques and procedures used for approaching and protecting the crime scene.

Polygraphy deals with the specific detection of deception in relation to criminal investigation.

Forensic toxicology is the study of the effect of drugs and poisons on/in the human body.

Forensic pathology is a field in which the principles of medicine and pathology are applied to determine a cause of death or injury in the context of a legal inquiry.

Forensic dactyloscopy deals with the study of fingerprint principles in criminal investigation.

Forensic Specialties

Forensic accounting is the study and interpretation of accounting evidence.

Forensic anthropology is the application of physical anthropology in a legal setting, usually for the recovery and identification of skeletonized human remains.

Forensic archaeology is the application of a combination of archaeological techniques and forensic science, typically in law enforcement.

Forensic astronomy uses methods from astronomy to determine past celestial constellations for forensic purposes.

Forensic botany is the study of plant life in order to gain information regarding possible crimes.

Forensic Specialties

Forensic chemistry is the study of detection and identification of illicit drugs, accelerants used in arson cases, explosive and gunshot residue.

Computational forensics concerns the development of algorithms and software to assist forensic examination.

Criminalistics is the application of various sciences to answer questions relating to examination and comparison of biological evidence, trace evidence, impression evidence (such as fingerprints, footwear impressions, and tire tracks), controlled substances, ballistics, firearm and toolmark examination, and other evidence in criminal investigations. In typical circumstances, evidence is processed in a crime lab.

Digital forensics is the application of proven scientific methods and techniques in order to recover data from electronic / digital media. Digital Forensic specialists work in the field as well as in the lab.

Forensic Specialties Forensic document examination or questioned

document examination answers questions about a disputed document using a variety of scientific processes and methods. Many examinations involve a comparison of the questioned document, or components of the document, to a set of known standards. The most common type of examination involves handwriting wherein the examiner tries to address concerns about potential authorship.

Forensic DNA analysis takes advantage of the uniqueness of an individual's DNA to answer forensic questions such as paternity/maternity testing or placing a suspect at a crime scene, e.g., in a rape investigation.

Forensic Specialties

Forensic engineering is the scientific examination and analysis of structures and products relating to their failure or cause of damage.

Forensic entomology deals with the examination of insects in, on, and around human remains to assist in determination of time or location of death. It is also possible to determine if the body was moved after death.

Forensic Specialties

Forensic geology deals with trace evidence in the form of soils, minerals and petroleum.

Forensic limnology is the analysis of evidence collected from crime scenes in or around fresh water sources. Examination of biological organisms, in particular, diatoms, can be useful in connecting suspects with victims.

Forensic Specialties

Forensic linguistics deals with issues in the legal system that requires linguistic expertise.

Forensic meteorology is a site specific analysis of past weather conditions for a point of loss.

Forensic odontology is the study of the uniqueness of dentition better known as the study of teeth.

Forensic optometry is the study of glasses and other eye wear relating to crime scenes and criminal investigations

Forensic psychology is the study of the mind of an individual, using forensic methods. Usually it determines the circumstances behind a criminal's behavior.

Forensic seismology is the study of techniques to distinguish the seismic signals generated by underground nuclear explosions from those generated by earthquakes.

Forensic serology is the study of the body fluids.

Main Sources of Physical Evidence

A. The Crime Scene

B. The Victim

C. The Suspect and His Environment

What will Evidence Collected at a Scene Do

for Investigation?

Importance of Evidence Collection in Investigation

May prove that a crime has been committed

Establish key elements of a crime Link a suspect with a crime scene or a

victim Establish the identity of a victim or

suspect Corroborate the verbal witness testimony Exonerate the innocent Give investigators and detectives leads to

work with in the case

The relationship of Forensic Science and Criminal

Investigation begins at the scene of the crime when

investigators start processing the crime

scene.

Physical evidence can establish that a crime has been committed or it can provide a link between a crime and its victim or

between a crime and its perpetrator

Did you Know?

According to The Innocence Project (2008) "Eyewitness misidentification is the single

greatest cause of wrongful convictions nationwide, playing a role in more than 75%

of convictions overturned through DNA testing."

Still, the criminal justice system profoundly relies on eyewitness identification and

testimony for investigating and prosecuting crimes (Wells & Olson, 2003).

Medico-Legal

CONDUCT EXAMINATION ON PERSONS INVOLVED IN PHYSICAL INJURY CASES AND SEXUAL OFFENSES.

CONDUCT AUTOPSY, EXHUMATION, SKELETAL AND ODONTOLOGICAL EXAMINATIONS TO DETERMINE THE CAUSE OF DEATH AND IDENTITY OF PERSONS.

CONDUCT HISTOPATHOLOGICAL AND SEROLOGICAL EXAMINATIONS TO DETERMINE EXACT CAUSE OF DEATH AS WELL AS THE PRESENCE AND TYPE OF HUMAN BLOOD.

CONDUCT DNA ANALYSIS FOR PERSON IDENTIFICATION. CONDUCT LECTURES TO DIFFERENT POLICE/ MILITARY

INSTITUTIONS, GOVERNMENT AGENCIES AND PRIVATE / PUBLIC SCHOOLS.

ORIENT AND TRAIN NEW PERSONNEL AND OJT ON THE FUNCTIONS AND CAPABILITIES ON THE DIVISION.

CHEMISTRY DIVISION

Conduct Qualitative and Quantitative Examination of Dangerous Drugs under RA 9165 as well as volatile substances under PD 1619.

Conduct examination of explosives and/or explosive ingredients. (PD 1866)

Conduct examination of Firearms and Paraffin casts for the presence of Gunpowder Nitrates.

Conduct Chemico-Toxicological examination of human internal organs, gastric contents, blood water and food sample and other substances.

Conduct examination of fake products in case of unfair trade competition.

CHEMISTRY DIVISION

Conduct blood alcohol determination. Examine urine and other body fluids for the presence

of dangerous drugs. Conduct researches and training related to the cases

being examined. Give lectures on Forensic Chemistry and Toxicology to

various schools, universities, police training centers and other investigative units.

Testify and give expert opinion in court. Respond to queries of all investigative units and render

expert opinion regarding matters related to the application of chemical principles for the purpose of assisting investigators in developing investigative leads.

Conduct Field laboratory work and clandestine laboratory investigation.

Conduct examination of evidence firearms, fired bullets/cartridge cases, shotgun shells, wads, pellets and related specimens recovered from the crime.

Conduct test firing of evidence firearms of different caliber;

Conduct scene of crime operations and field laboratory works;

Determines the classification of firearms as to power, pursuant to RA 8294;

Conduct lectures, briefings and seminars on firearm identification;

Appear in Court as Expert Witness; and Perform such other functions as may be directed

by the Director, Crime Laboratory.

FIREARMS IDENTIFICATION DIVISION

Responsible to the Dir, CL for the examination of all fingerprint evidence of criminal nature.

Supervise the technical training of the division personnel with regards to dactylosycopy so as to improve their knowledge and techniques of examination and analysis.

Provide lectures on the science of Dactyloscopy to PNP School and other units of the AFP.

Provide fingerprint expert witnesses in civil and military courts for the purpose of interpretation of dactyloscopic reports on the scientific examination performed.

Develop, lift and preserve latent print gathered at the crime scenes subsequently takes fingerprint of suspects and criminal.

FINGERPRINT IDENTIFICATION DIVISION

FINGERPRINT IDENTIFICATION DIVISION

Examine, compare and determine the identity or non-identity of all questioned finger, palm and footprints.

Assist in establishing identities of deceased persons whose cadavers and beyond recognition.

Classify, verify, and file all Fingerprint cards based on Henry System with FBI Modification and Extension.

Maintain index (3x5) card of cross-reference of persons by name whose fingerprint cards are on the Master File.

Examination of Questioned Signatures Handwriting Examination Examination of Document suspected to have been

Altered/Erased. Decipherment of Secret Writings Examination of Sequence of Entry Paper and Ink Comparison Typewriting Identification Examination of Counterfeit Bills Conduct lectures to PNP, AFP and other government

agencies. Conduct Field Laboratory Works Attend court Duties.

QUESTIONED DOCUMENT EXAMINATION DIVISION

Criminal Investigation Domestic Issues Employees Theft/Fraud Unfair Dismissal Pilferage Insurance investigation False and Malicious Allegations Sexual Harassment Pre-employment/periodic screening

POLYGRAPH DIVISION

Conduct analysis and comparison of specimen to determine its nature, composition, quality or source such as hair, fibers, debris, metals, paints, woods, restoration of serial numbers of motor vehicles and firearms, ultraviolet examination in entrapment and buy-bust operations, bullet trajectory in shooting incidents and casting and molding of different types of impressions and tool marks examination.

Assist investigators in the proper collection, handling and preservation of physical evidence.

Conduct researches before their adaptation, give lectures, technical opinion and testimony in both civil and criminal courts.

PHYSICAL IDENTIFICATION DIVISION

PHOTOGRAPHY DIVISION

Photograph suspects and crime victims for personal identification;

Photograph evidence submitted to this laboratory before examination;

Conduct crime scene photography; Conduct comparative examination and analysis of

questioned photograph; Conduct lectures to different police/military training

institutions, gov’t agencies and public/private schools upon request;

Process black & white film and print to reduce and enlarge photographs;

Reproduce photographs and other printed matters; Sketch facial features of suspects based on actual

description by the witnesses or victims for identification; Attend court duties; and Maintain Crime Laboratory “Rogue’s Gallery”