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Forensic Science & Canadian Law
Transcript of Forensic Science & Canadian Law
By: Garielle Chen
What is Forensic Science?
Forensic Science is the scientific collection and analysis of physical evidence to aid in the investigation of
criminal law cases.
Different types of F Science
Transition to Blood Spatter and Fingerprints
How is it used?
Forensic scientists use the information and evidence from a crime scene in order to discover the perpetrator(s) of a crime; they apply their scientific knowledge to the evidence provided in order to draw conclusions to the details of criminal activity.
This information is highly significant in Canadian criminal law as offenders are assumed innocent until proven guilty. The work of these scientists thus bring criminals to justice by providing evidence for police and prosecutors in preliminary hearings and court trials.
Specialty subsections of Forensic Science include:
the study of the effects, nature, and detection of alcohol and drugs
the study of bite patterns, and dental diseases and structures
the scientific study of insects
the study of firearms and marks/striations on bullets
the study of the origin, nature, and courses of diseases
scientists in this field study the shape
and patterns of bloodstains
Forensic finger print scientists study and analyze the characteristics of varieties of fingerprints
How the evidence comes together
In order to accumulate this evidence various forensic scientists of different specialties must process the types of evidence left at crime scenes
Police and prosecutors require a substantial amount of circumstantial evidence to imprison a criminal.
Therefore,police may require forensic scientists of different subdivision specialties to solve a crime
The analysis of fingerprint evidence
THE IMPORTANCE OF FINGERPRINT FORENSICS
Fingerprints are arguably the most significant piece of evidence regarding crime scene investigations as it is the most commonly used forensics evidence worldwide and matches or outnumbers all other forensic casework in most jurisdictions
This is because the fingerprint is proven to be a very prominent, permanent and unique characteristic to the human race
fingerprints develop before birth (during the 12th week of pregnancy). While other physical characteristics can very fingerprints remain unchangeable and irremovable.
except for the removal of a finger or diseases/surgery that cause deep scarring the fingerprint will remain permanent until decomposition after death
No two finger prints have been found to be alike; over 100 years of research and testing concluded that each person's fingerprint will have unique, varying characteristics
Not to mention being far more reliable and accurate than previous methods
Fingerprint analysis today is very precise and reliable; this method has been used for over 100 years on international levels to identify victims, witnesses, and criminals at crime scenes
No fingerprints have been discovered identical according to billions of human comparisions in automated computer analysis
Fingerprint evidence can be extremely accurate for identifying suspects:
However, fingerprint analysis has not always been so precise and advanced. The analysis of fingerprint has only been used a method to identify criminals since the 19th century.
HISTORY OF FINGERPRINT FORENSICS
It is only because of the history of research done on this topic that we are able to precisely identify individuals by their fingerprint.
Dr. Henry Faulds
The British Surgeon-Superintendent of Tokyo's Tsukiji Hospital
claimed fingerprints could be obtained with printer ink
studied "skin furrows" after noticing fingerprints on prehistoric pottery
recognized the importance of fingerprints as means of identification and created a method of classification of prints
published article in scientific journal called "Nature" discussing fingerprints as a way to personally identify an individual
Sir Francis Galton
collected and gathered around 8,000 fingerprints to analyze
published book called "Fingerprints" in 1892 that outlined the first fingerprint classification system in existence
classified prints based on three patterns; whorls, loops and arches
Argentine Police Officer
made the first criminal fingerprint identification
identified Francisca Rojas; a woman who killed her two sons then cut her throat to frame her lover of the crime
Vucetich matched the bloody fingerprints on a door handle to Rojas
she was proved to be the murder and confessed to the crime
Vucetich's record of Francisca Rojas' fingerprints
Sir Edward Henry
Commissioner of the Metropolitan Police of London
contributed to Sir Francis Galton's classification system
created his own fingerprint classification system based on direction, flow, pattern, and ridge characteristics
The Henry Classification System
became the primary method of fingerprint identification throughout most of the world today
The past versus now
The contribution from these forensic pioneers helped form personal fingerprint identification that is now used as evidence from crime scenes. This method identification has been shown to be instrumental in solving various famous crimes.
How Fingerprint Identification
Classification of Fingerprints
How Modern Fingerprinting Works
The Automated Fingerprint Identification System
Prior to the existence of computer law enforcement officials had to manually process and identify and individual's fingerprints
A decade after computers were created the Japanese National Police Agency created an electronic fingerprint matching system called:
This database became popular on an international level, and was used to aid in criminal investigations around the world.
The system advanced in 1999 to the IAFIS
(The Integrated Automated Fingerprint Identification System)
and is now used to analyze fingerprints for Canadian crime investigations today.
How does the IAFIS work?
The IAFIS is responsible for maintaining computerized fingerprint storage and search program.
In Canada, the fingerprints of charged individuals are scanned and captured in the system using a
program; a laser scanning device that replaced the traditional ink and paper method.
This system converts the capture, search, and storage of both crime scene and arestee finger & palm prints.
Fingerprint Forensics works by collecting, analyzing and comparing fingerprints using a specific knowledge of characteristics that make the fingerprint identifiable and matchable to a person.
What characteristics make the fingerprint identifiable? What do fingerprint analysts look for when evaluating a person's prints?
While Fingerprints may appear to look the same to the average person fingerprint specialists can distinguish prints by their pattern and characteristics.
Fingerprint analysts classify fingerprints by their ridge characteristics.
These features include:
also known as a "dot" or an "island"
also known as a "fork"
the point at which the ridge ends
(also known as minutiae points; points where the ridge structure changes)
Fingerprints are made up of ridges; lines on the finger and palm that create shapes and patterns .
the point at which a single ridge splits into two ridges
ridges that are significantly shorter than the average ridge length
a single ridge that divides and reunites to continue as a single ridge
Fingerprint analysts also evaluate the overall pattern and shape of the fingerprint. This is divided into 3 general groups:
ridges flow in from one side, loop around, and exit through the same side it entered
ridges form circularly around the central point of the finger
ridges flow in from one side of the finger, rise in the center making an arc, then flows out the other side
On average there are 125 unique ridge characteristics on a fingerprint. In Canadian law, fingerprint analysts must find at least 11 identical characteristics to prove it as a match to the accused in court.
Approximately 60% of people have loop prints, 35% have Loops, and only 5% have arch patterned prints
DID YOU KNOW?
Livescan is a real time identification system (RTID) this allows fingerprints to be quickly examinated and compared to the known offender database. This system allows results to return to the police station in as quick as 5 minutes.
The Toronto Police were the first agency in Canada to use real time fingerprinting in 2005.
How to become an expert
An expert in fingerprint identification would
likely obtain a career as a fingerprint analyst or fingerprint technician.
What job is for experts?
A fingerprint analyst's job is to use lab equipment and their forensic science knowledge to analyze fingerprints gathered from a crime scene.
A fingerprint technician will gather and analyze prints but will also work to help reconstruct events of a crime scene with the gathered fingerprint data.
Qualifications/Education of an Expert
To obtain either jobs an individual would have to become an expert in both forensics science and Dactyloscopy; the science of fingerprint identification.
To become an expert in this field a person would first have to gain these qualifications of education:
A Bachelors or Masters:
Arts in Social and Criminal Justice, Forensics
Science in Criminal Justice
Science in Biological Science
Science in Forensic Science
These courses cover the topics a fingerprint specialist would need to know in order become knowledgeable in both forensic sciences and Canadian law:
Introduction to Canadian Criminal Justice System
Crime Scene Investigation Procedures
Principals of Judicial Practice
However, for a forensic scientist may need to take advanced specific courses in order to become certified for becoming a fingerprint specialist. These courses entail coursework on the following topics:
The DNA of fingerprints
The Scientific Basics of Classifying, Recording, Comparing Fingerprints & Palm Prints
The Integrated Automated Fingerprint Identification System
What would a Print Specialist need to do?
A specialist in identifying fingerprints would work with law enforcement to solve crimes. They would often have to complete various tasks related to both forensic sciences and Canadian law. This involves having skills for particular tasks:
On average a Canadian Fingerprint Specialist whether being an analyst or technician makes around $55,000 a year
examine, test, and analyze evidence
collect fingerprint evidence without destroying/altering crime scene
use the IAFIS and have knowledge of the system to process, search, and compare fingerprints
writing detailed reports
making verbal testimonies
translate complex scientific evidence to an explanation understandable to appropriate audience
Research and Problem-Solving Skills:
evaluate evidence to make connections/ theories about crime
record results of findings, tests, and test results
identify alternative/ possible solutions to unexpected issues
Who do fingerprint specialists work for?
Federal, Provincial and municipal government
These fingerprints can be identified at crime scenes can be in three general forms:
these prints are easily visible to the human eye because the person who left the impression had their finger in some type of liquid or powder substance.
At crime scenes these types of prints are most likely to be visible because the individual's hands were covered in blood
These prints are not visible to the human eye but can be made visible with the use of a powder/ chemical agent. Fingerprint analysts primarily identify these types of prints in crime scene investigations.
This is how these forensic scientists uncover latent prints:
Impressed prints also leave visible impressions because the hand has been pressed on a soft material. (Ex.soap)
The Farrow Case:
The neighbors of the married couple Thomas and Ann Farrow found the couple's beat up dead bodies in their paint shop in South London.
This high-profile murder was solved by using a new fingerprint identification technique.
This murder was solved when a clear fingerprint identified the killers of the couple
It belonged to two brothers who murdered the couple in order to steal their cash receipts from their cash box. This evidence was the only solid proof that the brother were at the crime scene, and ultimately led to their conviction on May,23, 1905.
The Night Stalker
This case took place between the dates of :
Fingerprint evidence became crucial to finding the famous South Californian serial killer nicknamed "The Night stalker".
This killer killed 13 individuals by breaking into their house and murdered them as they slept.
However, this man was brought to justice when a teen noticed a suspicious looking car and wrote down its license plate.
Coincidentally this turned out to be the murder's car. Police decided to search it, and discovered one key evidence that solved the crime. It was a fingerprint; this print was analyzed and identified the killers as a 25 year old man named Richard Ramirez. He was captured, and sentenced to death. He currently sits on the death row.
What is Blood Spatter Forensics?
Blood Spatter Forensics is the examination of bloodstain characteristics in order to provide an explanation of the physical events that occurred at a crime scene.
Forensic scientists in this field can receive a substantial amount of information from bloodstain patterns by focusing on the characteristics of the blood spatter and what they mean.
How does this information help solve crimes?
So what can Blood spatter specialists determine from a crime?
An experienced blood spatter specialist can determine a large amount of information just from viewing the blood patterns at a crime scene. Blood stain characteristics can tell an analyst:
The distance from the blood source to the target
The direction of the blood travel & its impact angles
The nature of the level of impact used to cause bloodshed
The type and velocity of object used to cause the bloodshed
The order of the events causing bloodshed
The work of a bloodstain specialist aids with the investigation of a crime because it can be used to find out various types of various information about the crime.
this information can:
confirm or prove the position of a victim, witness,suspect or defendant
determine if there is evidence of a struggle, or if the attack was "one sided"
the position and movements of the victim during the assault
the number of blows
the order of the inflicted wounds
how long ago the crime was committed
whether the death was intimidate or delayed
How is blood spatter forensics used?
A blood spatter specialist is able to make conclusions on events from a crime scene by primarily using biology, math and physics.
Blood spatter analysts like fingerprint analysts can evaluate evidence by looking for particular patterns or characteristics.
What are the characteristics of spatters?
What can they tell about a crime scene?
These scientists need to know the anatomy of the human body and most importantly the characteristics of blood.
blood contains both liquids
(plasma and serum)
(blood cells,platelets, and proteins)
. Blood is a liquid when it is inside the body, but as you might know it clots and thickens when you receive a cut.
Blood spatter specialists use their knowledge on the human body to understand important information to aid in crime scene investigations.
If there are blood clots in bloodstains it can indicate that the victim's death was prolonged because the person was bleeding out for some time.
This occurs when there is both forward and backward blood spatter from the exit wound. The pattern of the blood may vary but typically there is a fine mist in the forward spatter and fewer, larger drops of blood behind the exit wound
This occurs when an assailant winged a bloodstained object backwards; some of the blood from the object creates spatter from the swing. Blood specialists can tell which direction the object of impact came from & how many times the victim was hit based on the shape of spatter
A stabbing is called a sharp force injury and is identified by specialists when there are more linear pattern of stains
A blood spatter analyst can identify whether or not if a victim was beaten based on the the surface area of the impacting object; the larger the surface area the more blood it will collect, producing drops of similar sizes.
The shape and size of blood spatter is affected by the level of force of the impact. There are 3 general levels of velocity that cause general spatter shapes:
Low velocity (passive)
This is blood that falls at the speed/ force of normal gravity. These low force impact spatters are large and circular in shape with diameters of 4mm or more & usually fall from an open wound rather than a strike or attack.
Medium velocity spatter are considered impacts that produce more force than normal gravity and are categorized by attacks faster than 25ft per second. This type of spatter usually occurs from attacks such as stabbings. These spatters appear to be a random pattern of varying sizes of spatters with the largest drops of blood broken into smaller spatters with diameters of 2-4 mm.
This type of spatters occurs from high impact attacks (gun shots, explosions, high speed car collisions) categorizing at a speed over 100 ft per second. High velocity spatter is very small measuring with diameters of less than 2mm. This pattern is mist-like in appearance.
For clarification on the levels of blood spatter velocity watch this video clip:
*add path for video
Famous Cases solved by Blood Forensics
The criminals of this crime has been brought to justice because of blood evidence that proved them guilty for their actions
Australian biologist and physician
named and standardized different types of blood
found 2 distinct reactions from the blood experimentation- clumping and repelling
Dr. Leon Lattes
developed a procedure to test blood stains on fabrics and other materials
invented the first way to test for antibiotics in dried blood flakes in 1932
Australian biologist and physician
helped individualize blood in 1940 by discovering the rhesus factor in blood; an inherited trait found in the protein on top of the surface of red blood cells
Blood specialists discovered that around 80% of the human population were "secretors"; have specific types of antigens, proteins and antibodies in their bodily fluids or tissue
this helps in crime scene investigations as suspects can be narrowed down by the characteristics of their blood
The Chamberlain Case
This case occurred in Central Australia in 1980 when a family took a camping trip near a rock formation called Ayer Rock
Contributions to Blood Spatter Forensics
Lindy Chamberlain put two of her children ( 4 year old Reagon and 10 week-old Azaria) to sleep in their tents
Once she returned she told the other campers a dingo took her baby
She told a park ranger the story and showed him the bloody blanket and bloodstained items in the tent
The ranger took this evidence but did not take the Chamberlain's bloody clothes until long afterwards
This case was solved when Lindy Chamberlain's blood group was found in a nearby cave
This raised the police's suspicion and forensics did a fluorescent examination of Azaria's jumpsuit only to find a blood mark consistent of slitting a throat
Most of the evidence in this case were seen invalid in court. The blood pattern evidence lead to both Mr. & Mrs. Chamberlain's conviction
Fingerprint and blood forensics help solve criminal cases by providing the police with crucial information by finding out the specifics through the evaluation of DNA evidence
What does one need to become a blood spatter specialist?
To obtain a job within the field of blood pattern forensics you will need to meet the bare minimum requirements for Blood Pattern Analysts:
* a bachelors degree or equivalent in a field related to bloodstain pattern analysis
* a high school diploma with at least 4 years of relevant work experience
*an associate's degree with at least 2 years of relevant work experience
What else would someone need?
Canadian Post-Secondary Choices
To Study Forensics:
a strong educational background in math and science
especially biology, chemistry, and physics as it is crucial to have this skill for the evaluation of blood spatter movement rates and blood DNA identification
jobs in forensics and law enforcement often require employers to look into a potential employee's personal history and criminal background
specific blood splatter training
usually a prerequisite to take at least 40 hours of blood pattern specified courses
receive a mark of at least a 75% on the 4 sectional Bloodstain Pattern Analysis Certification Exam
employers also look for people who have a high moral character, good reputation, and integrity
similar to fingerprint analysts blood pattern scientists on average make around $55,000 a year