Forensics notes

Ridgeline Forensics notes

                                    

 

forensic Science – PBL Curriculum:

Ch. 1 – Intro to forensic science:

  1. Purpose of this unit:
    1. What is forensic science?
      1. The application of science to law – the application of science to the criminal and civil laws that are enforced by police agencies in a criminal justice system.

 

  1. What does it encompass?
    1. Encompasses criminalistics, digital and multimedia sciences, engineering science, general, jurisprudence, odontology, pathology/biology, physical anthropology, psychiatry/behavioural sciences, questioned documents, toxicology, and even more!
  1. What is a forensic scientist?
    1. An individual that acquires physical evidence at a crime scene, or works in a laboratory to decipher what the evidence is. 
    2. What they are not is someone who puts the pieces of the puzzle together to form what may have happened at the crime scene – that is for the detective to do.

 

  1. History of forensic science
    1. 3rd-century Chinese manuscript Yi Yu Ji (A Collection of Criminal Cases)
      1. What did this manuscript have to do with forensic science?
        1. A Chinese coroner determined that a man was killed prior to being burned using pigs to look for ash in the mouth.
  1. A Treatise on Forensic Medicine and Public Health by Francois-Emanuel Fodere (French physician)
    1. What did this Treatise provide scientists?
      1. A physician’s guide to the workings of the human body – 1798

  1. Chemist Carl Wilhelm Scheele (Sweden)
    1. What did Dr. Scheele produce?
  1. First successful test for determining arsenic in a person’s blood
  1. Father of Toxicology – Mathieu Orfila (Spain)
    1. When and why was the first toxicologist used in a trial?
      1. The first treatise on the detection of poisons and their effects on animals. First used in 1839 by Scottish chemist James Marsh on the detection of arsenic in a victim’s body.

  1. Alphonse Bertillon’s system vs fingerprinting (describe the history and contributors of both)
    1. What was the Bertillon system? What did it measure?
    2. 1879 Alphonse’s system of anthropometry was to make several measurements of a criminal (head circumference, arm length, leg length, overall height, ability to bend at the waist, etc.

 

  1. When did fingerprinting start being used as a way to identify individuals?
    1. Fingerprints supplanted this system early in the 1900s as it was a more reliable way to identify individuals.
  1. What was the reason for the change from the Bertillon system to using fingerprints in the United States?
    1. The Bertillon system was not dependable, there are many people who have the exact same measurements, but no one has the same fingerprint
  1. Albert S. Osborn and his book “Questioned Documents”
    1. What does this book discuss?
      1. A book still considered a primary reference for document examiners; developed the fundamental principles of document examination and was responsible for the acceptance of documents as scientific evidence by the courts.

 

  1. Is this book still used by forensic scientists today?
    1. Yes
  1. Edmond Locard and Locard’s exchange principle
    1. Who was Edmond Locard?
      1. Locard asserted that when two objects came into contact with each other, a cross-transfer of materials occurred. He believed that every criminal can be connected to a crime by dust particles carried from the crime scene. He pioneered the way for crime laboratories to be established in police departments after WWI.
    2. What is Locard’s exchange principle?
      1. Every contact by a criminal leaves a trace
  1. How/where did Edmond Locard set up the first “crime lab”?
    1.  He pioneered the way for crime laboratories to be established in police departments after WWI.
  1. Modern-day advances (such as DNA, entomology, and others?)
    1. When was DNA first used to solve a criminal case and who did it help convict?
      1. DNA typing was first used in 1986 in a criminal case to convict Colin Pitchfork for the murder of 2 young English girls.
      2. Entomology is the study of bugs and how they affect a decaying body
      3. The development of the microscope was huge
      4. The invention of the comparison microscope for ballistics
  1. What is entomology?
    1. Entomology is the study of bugs and how they affect a decaying body

 

  1. How is entomology used in forensic science?
    1. It is used to tell how long ago a person died and how
  1. How did the invention of the microscope aid in the development of Forensic Science?
    1. It allowed scientists to view DNA molecules and smaller objects that could be important when solving a case
  1. How are crime labs “run” today (public vs. private)
    1. Public – run by the state or local governments, limited by funds, used only for criminal cases
    2. Private – specialised and can work on both criminal and civil cases

 

  1. Court cases that set the standards for allowing forensic evidence into the courtroom. This is your first Capstone Project to complete. Please see the additional handout for this assignment.

  1. Federal Rules of Evidence (particularly rule 702) – (Required)
    1. What was this case about?
  1. A witness who is qualified as an expert by knowledge, skill, experience, training, or education may testify in the form of an opinion or otherwise

 

  1. What qualifies a person to be an “expert” in their field enabling them to testify in court?

 

  1. 1993 Daubert v. Merrell Dow Pharmaceuticals, inc. – (Required)
    1. What was this case about?
      1. Overturned the Frye test and set recognized new guidelines for what kind of scientific evidence would be admissible in court – set the courts up as “gatekeepers” of how scientific evidence would be allowed in courts.
  1. How did this ruling affect the Frye rule?

 

  1. How did this alter the way courts allow access to forensic evidence in the courtroom?

 

  1. United States v. Starzecpyzel – (Optional)
    1. What was this case about and how was evidence allowed into the courtroom?
      1. This was about forgery and expert testimony was allowed under rule 702 but not under Daubert
  1. Kumho Tire v. Carmichael – (Required)
    1. What was this case about?
      1. The Daubert “gatekeeping” not only applied to scientific expert testimony but to all expert testimony – Rule 702 does not distinguish between scientific knowledge and technical or other specialised knowledge, but makes clear that any such knowledge might become the subject of expert testimony,
  1. What/who qualifies as an expert witness?

 

  1. United States v Prime – (Optional)
    1. What was this case about?
      1. Fraud case (handwriting) handwriting experts are not part of the scientific community but ARE part of the “technical” community thus their testimony would be allowed in court and could be cross examined.
  1. What is the difference between the scientific community and the “technical” community?

 

  1. Coppolino v State (of Florida) – (Required)
    1. What was this case about?

Coppolino was tried and charged for the murder of his wife

 

  1. How was this evidence allowed in court if there had not been “general acceptance” of this type of test?
  1. A completely novel procedure for detecting succinylcholine chloride was devised and allowed in court.

 

  1. Casey Anthony – CSI Effect? Case study
    1. Casey Anthony trial – https://www.crimemuseum.org/crime-library/famous-murders/casey-anthony-trial/
      1. Questions:
        1. How long, and why did Casey Anthony wait to report her daughter missing?

30 days

 

  1. What evidence was presented against Casey Anthony?

There was hair and fibres found in the trunk of her car, grandpa was missing tape

  1. How was Casey Anthony acquitted of the murder of her daughter?

  1. What is the CSI effect? – 

The CSI effect is because tv has shown us we can have a crime scene and solve it in an hour that it happens like that in real life

  1. https://www.oxfordhandbooks.com/view/10.1093/oxfordhb/9780199935352.001.0001/oxfordhb-9780199935352-e-28
  1. Did the CSI effect have an effect on the Casey Anthony trial? – https://lawrecord.com/2011/08/11/the-case-of-casey-anthony-defending-the-american-jury-system/
  1. Caylee’s law – what is it and is it a law in AZ.? 

Caylee’s law says that if you’re a parent and your child goes missing you have to report it. Arizona does not have it

https://www.alcatrazeast.com/crime-library/criminal-law/caylees-law/

  1. Investigate: https://www.crime-scene-investigator.net/becomeone.html
    1. Investigate one or two of the job posting that you have an interest in and do a writeup of why it interests you (something other than pay/income), job description, job growth in that particular area, 
    2. Click on the article link to “Duty Description for the Crime Scene Investigator” by Mike Byrd.

 

  1. How should a crime scene be processed (what are the steps in detail)?

 

  1. Shirt examination lab – need shirt(s) with 2 types of hair on it – teach how to make a druggist fold and how to properly collect evidence. 

Ch. 2 – The crime scene

  1. Purpose of this unit:
    1. What are the 7 S’s of crime scene investigation?
      1. Secure the scene
      2. Separate the witnesses
      3. Scan the scene
      4. photograph the scene
      5. Sketch the scene
      6. Search for evidence
      7. Secure and collect the evidence
  1. Secure and preserve the crime scene – who, how, how big of an area is secured, witnesses, etc.

the first responding officer and his first priority is the victim and those that need medical attention. he’s got to keep the general public out

  1. Record the crime scene – who, how (what is the process)

3 parts: 

Photograph the scene as quickly as possible

rough sketch- contains an accurate picture of the dimensions and objects in the scene, does not need to be neat, needs to have a north south east, and west; just needs to be accurate

Final sketch: a neat sketch of the crime scene: they can capture things some people may not have noticed

Notes: Keeping track of people who entered and exited the scene, notes need to be detailed enough to look back on months or years later

  1. Conducting a systematic search – who, how (types of patterns), why, what tools might be used

The kind of crime

Where the crime takes place

How big the crime scene is

grid searches, line searches, spiral searches, rays search, quadrant search

  1. Collecting, Handling, and Packaging physical evidence; Collecting, Handling, and Packaging of biological evidence

  1. What is the Chain of Custody and how is it maintained?

  1. Obtain standard/reference samples
  1. JonBenet Ramsey – https://www.crimemuseum.org/crime-library/cold-cases/jonbenet-ramsey/
    1. Crime scene – https://www.pinterest.com/OsnapitzLibbyy/jonbenet-crime-scene-photos/
    2. Crime scene – https://www.thecrimemag.com/a-heartbreaking-look-back-at-jonbenet-ramseys-murder/
      1. Questions:
        1. Describe the crime scene.
  1. How was JonBenet eventually found?

  1. How would you describe the police response (give examples)?

  1. How was the evidence handled?

  1. How was the search of the premises (the house and yard) handled? Give specific examples.

  1. Was the chain of custody kept intact or broken? Tell me why you think so.
  1. How could the police have done a better job at securing the crime scene? Give specific examples.

  1. Scott Peterson Crime – https://www.biography.com/news/scott-peterson-laci-murder-trial-timeline-facts
    1. Questions:
      1. What/where was the crime scene for the Scott Peterson case?
        1. The Scott Peterson case was where Scott was tried for the murder of his wife and unborn son
        2. The crime scene was off the shoreline of the San Francisco bay

  1. What evidence was found at the crime scene?
    1. A single hair that came from Laci was stuck to pliers on Scotts boat

 

  1. How did not having the body of Laci Peterson affect the initial investigators?
    1.  
  1. How did the investigation change once the body of Laci Peterson washed up on the shore?
    1. At first, it was just a missing person case, they couldn’t tell if it was a homicide until they had bodies. 

  1. What evidence was presented at the trial?
    1. Scott sold his wife’s car before she was killed
    2. He refused to take a polygraph
  1. As a crime scene specialist, how would you secure this type of crime scene?

I would take photos of every angle and object there, collect the foetal remains to send to the lab, take a rough sketch of the crime scene, and collect DNA samples from both the wife and the unborn child. 

  1. What are the differences between the JonBenet and Scott Peterson cases?
  1. Rough sketch and finally cleaned up a sketch of a crime scene – Barbie doll set with a couch, tv, rug, bookshelf, etc.

Chapter 3: physical evidence

  1. Purpose of this unit: explain difference between identification and comparison of physical evidence 
    1. Common types of physical evidence: 
      1.  almost anything can be physical evidence.
      2. you cannot rely on a list of categories. 
      3. Physical evidence is used to be collected and analyse

 

  1. Documents: any handwriting or typewriting 

 

  1. blood, semen, saliva- liquid or dried, is it human or animal? 
  1. Drugs:any substance in violation of laws regulating sale, manufacture, and distribution

 

  1. Explosives: any device containing an explosive charge as well as objects that are suspected to contain residues of explosive

 

  1. Fibres: any natural or synthetic fibre whose transfer may be useful in establishing relationship between objects/people

 

  1. fingerprints:  all prints of this nature hidden (latent) and visible

 

  1. firearms and ammunition: any firearm, as well as discharged or intact ammunition

 

  1. glass: any glass particle or fragment that may have been transferred to a person or object during the rime 

 

  1. hair: any animal or human hair present that could link a person to a crime

 

  1. impressions: markings, shoe prints, depressions in soft soils, and all other forms of tracts

 

  1. organs and physiological fluids: body organs and fluids are submitted for analysis to detect possible existence of drugs and poisons

 

  1. paint: any paint, liquid or dried, that may have been transferred from the surface of one object to another during commission of the crime

 

  1. petroleum and products: any petroleum products removed from suspect or crime scene

 

  1. plastic bags: disposable polyethylene  bag such as a garbage bag may be evidence in homicide or drug sale

 

  1. plastic, rubber, and other polymers:remnants recovered at the crime scenes may be linked to object recovered 

 

  1. power residues: any item suspected of containing powder residues resulting from the discharge of a firearm 

 

  1. Serial numbers: category includes all stolen property submitted to lab for restoration of erased ID numbers

 

  1. soil and minerals:  all items containing soil or minerals that could link person/object to particular location

 

  1. tool marks: contains any object suspected of containing impression of another object that served as a tool in the crime

 

  1. vehicle lights: examination of vehicle lights and tail lights is normally conducted to determine whether a light was off or on during time of impact

 

  1. wood and other vegetative matter: any fragments of wood, sawdust, shavings or vegetative matter discovered on clothing, shoes, or tools that be a link to person/object linked to a crime location 

 

  1. Identification and comparison of physical evidences: 
    1. examination is undertaken for identification or comparison purposes
    2. identification: determination of the physical or chemical identity of substance with as near absolute certainty as existing analytic techniques will permit
    3. Identification: the object of identification is to determine the physical or chemical identity with as near absolute certainty as existing analytical techniques permit
    4. process of identification first requires adoption of testing procedure that give characteristic results for specific standard materials

 

  1. Second identification: 
    1. once test results established they will be permanently recorded and used repeatedly to prove identity of materials 
    2. identification also requires that the number and type of tests needed to identify a substance be sufficient to exclude all other substances

 

  1. comparison analysis:  
    1. subjects specimen and a standard/reference specimen to the same tests and examinations for ultimate purpose of determining whether or not they have a common origin

 

  1. 2 step procedure- 1st: 
    1. Crime laboratory frequently requested to identify the chemical composition of illicit drugs. May be asked to identify gasoline in residues covered from debris of fire
    2. Identification of blood,semn, hair, or wood are included for determination for species origin
    3. Comparative analysis has important role of determining whether or not suspect and reference specimen have common origin
    4. both standard/reference and suspect specimen are subject to same tests
  1. Comparison: Forensic comparison is two step procedure: 
    1. Combination of select properties are chosen from suspect and the reference specimen for comparison 

Once examination completed, forensic scientist must be prepared to render conclusion with respect to origins

  1. 2nd
  1. individual vs class characteristics
    1. individual characteristics: Evidence that can be associated to a common source with a extremely high degree of probability is said to possess individual characteristics
      1. It isn’t possible to state with mathematical exactness the probability that specimens are of common origin
      2. it can only be concluded that this probability is so high as to defy mathematical calculations or human comprehension
      3. Individual character examples” comparison of handwriting, comparison of striation markings, comparison of two fingerprints, etc
    2. class characteristics : Evidence associated only with a group that is said to have class characteristics- I.e blood types
  2. significance of physical evidence
    1. probability is a determining factor. high diversity of class evidence in environments makes their comparison very significant in context of criminal investigation

 

  1. Role of probability: To comprehend evidential value of a comparison, one must appreciate role that probability has in ascertaining the origins of two or more specimens
    1. Probability is the frequency of occurrence of an event
    2. Assessing values of: weakness of forensic science: inability of the examiner to assign exact or even approximate probability values to the comparison of most class physical evidence-very few statistical data from which to derive this info, gathering this kind of info is increasingly elusive. Primary endeavour of forensic scientists must be to create and update statistical database for evaluating the significance of class physical evidence 
    3. Cautions and limitations: 
      1. most items of physical evidence retrieved at crime scenes cannot be linked definitively to a single person or object 
      2. two or more objects found at crime scene- chances are they came from the same source
      3. evidential variations are not the same as natural: natural- occurs in nature evidential: does not occur in nature
  2. Forensic database 
    1. Fingerprints: integrated automated fingerprint identification system (IAFIS)
    2. DNA: combined DNA index system, (CODIS)
      1. Troy Graves- The Center City Rapist
    3. ballistics/guns/handguns: National Integrated Ballistics information network (NIBIN)
    4. Others? : PDQ- International forensic automotive paint data query- contains chemical and colour info pertaining to original automotive paint
    5. Shoe Prints: Shoeprint image capture and retrieved (SICAR)
    6. Crime scene show prints known as SICAR:
    7. National missing and unidentified persons system (NAMUS):
  1. Amanda Knox
    1. who all were accused of the crime? 
      1. Knox, Sollecito, Lumumba, and Guede
    2. What “evidence” did they have against amanda? 
      1. there was no evidence against her
      2. They found Knox’s DNA on the handle of the knife and kerches on the blade. There was also a bloody footprint on a bathmat, bra clasp, and a broken window. 
      3. She was guilty because she showed no remorse, went shopping after the murder, had sex with her boyfriend after and smoked weed, and lied during the investigation. During the night of the murder she met up with Patrick

 

  1. How was the case eventually overturned for Amanda? 
    1. The DNA evidence and fingerprints did not match up
  2. Who was eventually convicted for the murder 
    1. Rudy Guede-he lived downstairs- which is where parties happened all the time
  3. Where was Amanda when she was finally cleared of the murder and why was she there? 
    1. She was in Seattle because that is where she grew up. 
  4. Today she is an advocate for those who have been wrongly accused and Jason Hawking? 

Chapter 4: death 

 

  1. Role of forensic pathologist: Someone who studies death and disease- determines cause of death
    1. Coroner is an elected official
    2. history of coroner- 
      1. may not have medical degree
      2. Medical examiner is appointed and usually physician who is board certified
      3. history of coroner stems from king richard I for the purpose of collecting money and personal possessions from deceased families (death tax)

 

  1. what a pathologist might do at the scene of the crime
    1. protect scene and body
    2. removal of body in medically acceptable manner
    3. critical phase of death investigation will be preliminary reconstruction of events that preceded the onset of death, all significant details of scene is recorded 
    4. blood splatter and blood flow prints are documented
    5. tire marks or shoe prints must be documented 
    6. fingerprints must be processed and collected
    7. evidence dropped or discarded by perpetrator is collected
    8. weapons, fired bullets, and casings are collected
    9. photographs taken before scene is altered in any way
    10. critical phase of death investigation will be preliminary reconstruction of events that preceded the onset of death

 

  1. The cause and manner of death is done through autopsy which can only be performed by forensic pathologist

 

  1. cause of death
    1. primary objective of autopsy is to determine cause of death
    2. some common causes of death: blunt force injury, sharp force injury, sharp force injury, asphyxia, gunshot wound, and substance abuse

 

  1. blunt force injury
    1. cause by non sharpened object 
    2. can abrade tissue or cause contusion- arising from bleeding from tiny ruptured blood vessels
    3. being able to determine age of bruise is very problematic and unreliable
    4. sometimes contusion can take the shape of the offending object

 

  1. Sharp force injury
    1. come from weapons with sharp blades
    2. a cut is longer than it is wide
    3. a stab is deeper than it is long
    4. these types of scenes are very bloody, blood may be found at different locations throughout the crime scene
    5. important to look for defence wounds (forearms or legs) if there are none, victims may have been unconscious or tied up during assault. 

 

  1. Asphyxia
    1. interference with intake of oxygen- toxic gas or carbon monoxide
    2. death at fire is caused primarily by toxic gas carbon monoxide
    3. carbon monoxide binds to red blood cells and will be present after death which will indicate if victim was breathing at the time of the fire
    4. Hanging:
    5. victims die from loss of blood flow to/from the head and may show petechiae-blood vessels burst inside of eyelid
    6. important to note exactly how victim was found, position of nose, and type of knot used
    7. SMothering:
    8. blocking mouth or nose with some object
    9. these types of crimes are homicidal and accidental
    10. typically happens in infants or where victim is trapped under something

 

  1. gunshot wound
    1. the distance weapon was fired from a target is one of most important factors in characterising gunshot wound
    2. if firearm was fired from several feet away, it rules out suicidee
    3. autopsy must include determination of pagth/”wound path of projectile
    4. pathologist will collect all projectiles from body
    5. gunshot wound may not explain how victim died’ it can take several minutes or hours for person to bleed out or infection may be ultimate cause

 

  1. substance abuse 
    1. toxicological tests are performed every autopsy because it’s so common
    2. large problem in us
    3. not all illegal drugs lead  to death
    4. many drugs can be detected at very low levels
    5. drugs can cause death or be contributing factor to one’s death
    6. also source of acts of violence that lead to death 

Coroner history: 

The coroner originated in England during the 11th century. Originally, they were labelled “crowner” or “coronator. The word coroner derives from the Latin root word coroner, which is Latin for officer of the crown. The coroner system was first created when Richard I was in power. The king and the sheriff were concerned that they were not receiving all of the death tax money. King Richard thus appointed a coroner to keep track of all the deceased and make sure their taxes were paid. During 1194, Richard the Lionhearted officiated the coroner system. 

 

Works cited

Britannica, The Editors of Encyclopaedia. “coroner”. Encyclopedia Britannica, 27 Sep. 2007, https://www.britannica.com/topic/coroner. Accessed 13 September 2022.

  1. The autopsy- what is it and why is it done?

 

  1. autopsy in broadest sense
    1. The examination of the body after death
    2. Goal of autopsy is to determine cause of death and manner of death
    3. Cause of death determination includes the autopsy, history, history of death, witness statements, relevant medical records, and any crime scene investigation

 

  1. what kind of evidence can be recovered from autopsy
    1. Medical examiner carefully examines the victim to establish cause and manner of death
    2. Tissues and organs will be retained for pathological (disease)  and toxicological examination
    3. Arrangements made between examination and investigator to secure a variety of items that may be obtainable from the body for laboratory examination
    4. THe following can be collected and sent to forensic laboratory
      1. Victims clothing
      2. Fingernail scrapings
      3. Combings from head and pubic hairs
      4. Buccal swab
      5. Vaginal, anal, and oral swabs
      6. Recovered bullets from body
      7. Hand swabs form shooting victims
      8. Swabs of body areas suspected of being in contact with dna
      9. Hand stubs or swabs for gunshot residue analysis

 

  1. What types of examinations are done during an autopsy and why?

 

  1. external examination:
    1. Broad overview of condition of body and clothing
    2. Consists of classifying injuries-distinguishing between different types of wounds
  2. internal examination:
    1. Dissection of human body
    2. Remove all internal organs through y shaped incision beginning at top of each shoulder and extending to pubic bone
    3. weighing , dissecting, and sectioning each organ of the body
  3. Toxicology
    1. Internal examination is where toxicological specimens are taken
    2. Samples of blood,stomach content, bile, and urine
    3. Blood is tested to determine the presence and levels of alcohol and drugs
    4. Some drugs redistribute the blood after death and thus complicate the interpretation of postmortem blood levels of these drugs

 

  1. manner of death
    1. what is the difference between cause of death and manner of death
      1. Manner of death: relates to the circumstances that led to the fatal result
    2. what are the 5 manners of death
      1. Homicide
        1. Non accidental death caused by grossly, negligent, reckless, or intentional actions of another person
      2. Suicide
        1. Result of person taking their own life
        2. Must be determined that the individual carried out the act alone
        3. Victims personal history, psychiatric history, past attempts, past threats, or even a note will be taken into account
      3. Accidental
        1. There must not be an intent to cause harm on part of the perpetrator or victim
        2. All cases must have toxicology report carried out
        3. Autopsy should be able to correlate what the crime acne indicates
        4. Determination of manner of death in drowning, falls, and asphyxiation can be extremely difficult
      4. natural causes 
        1. Distinction between natural death and accidental is challenging
        2. Classification of natural death includes disease, chronic drug abuse, alcohol abuse, longtime exposure to natural toxins or asbestos
        3. Drug abuse has to be proven that a lethal amount was purposefully taken in order for it to be a suicide
      5. Undetermined
        1. When rational classification cannot be determined
        2. Can happen when the mechanism that caused the death cannot be determined by a physical finding in the autopsy-or lack of meaningful findings in the subsequent toxicology report. 
  2. estimating time of death:
    1. Pathologists can never give exact time of death- some factors can be analysed to determine approximate time of death
    2. Witness statements help with events leading up and after the crime, physical changes must be accounted for as well, 
    1. what is algor mortis, livor mortis, and rigor mortis?
      1. algor mortis:
        1. Results in the loss of heat by a body
        2. Body loses heat by 1 to 1 ½ degrees fahrenheit per hour until body reaches environment temp- can be used to determine time of death
        3. Factors that change this are ambient temp, body size, and victims clothing
      2. livor mortis:
        1. Results in settling of blood in areas of body closest to ground- occurs from 20 minutes to three hours of death ad continues up to 16 hours, after all point of lividity/colour is fixed
        2. Lividity can be blanched (turn white) when pressed until it becomes fixed. Good indicator that body was moved after death 
      3. rigour mortis:
        1. Results in shortening of muscle tissue and stiffening of body parts in the position at death (occurs within first 24 hours and disappears within 36 hours)
        2. Conditions that are hot can speed up this condition along with physical activity that occurred prior to death
        3. Individuals with limited muscle mass (infants, elderly, obese) may not develop rigour completely. 
    2. what does potassium levels in the eyevak fluids tell pathologists
      1. potassium eye levels: Forensic pathologists can determine amount of potassium in vitreous humour of eyeball and use it to approximate time of death
      2. The time at which potassium is released can be used to approximate the time of death
    3. What does the contents of the stomach tell a pathologist? Why is it important? 
      1. stomach contents: may help determine the location of the victim prior to death
      2. May also have undissolved pills 
    4. What does decomposition tell a pathologist?
      1. decomposition: once decomposition has set in, previous methods are not usable. After death two things take place: Autolysis and putrefaction

 

  1. Autolysis
    1. Self regulation of cell destruction by enzymes
    2. Dependent on mechanism of death
  2. putrefaction 
    1. Decomposition carried out by microorganisms such as bacteria
    2. Accompanied by bloating, discoloration, foul smell caused by accumulating gases
    3. Dependent on mechanism of death
  1. Role of forensics anthropologist: 
    1. Forensic anthropology is concerned with the identification and examination of human skeletal remains
    2. Examination of bones can reveal sex, age, race, and skeletal injuries
    3. Gender can be determined by the size of pelvis and skull
    4. Female pelvis is wider and more circular 

 

  1. recovering and processing remains
    1. Sites where human remains are found-treated a crime scene
    2. Scene must be secured and searched 
    3. All aspects of evidence must be documented and collected
    4. Aerial photograph, metal detectors, ground penetrating radar, infrared photography, cadaver dogs
    5. Every bone needs to be photographed, tagged, and sketched and documented in notes
    6. Height of when victim was alive can be estimated by measuring long bones of skeleton
    7. Anthropologist may help create facial reconstructions to identify skeletal remains

 

  1. How can facial recognition help forensic anthropologists?
    1. Identify skeletal remains
    2. Only dna is required for comparison 
    3. Can determine age, sex, and race 
  2. Determine victim characteristics
    1. What can a skeleton tell an anthropologist about the identity of the victim?
      1. Are the bones human?
      2. how many individuals are represented
      3. How long ago did the death occur?
      4. What was the victim’s age?
      5. What was the person’s sex? 
      6. What was the person’s ancestry?
      7. What was the person’s height? 
      8. Are there any identifying characteristics such as old injuries, disease, or unusual features?
      9. What was the cause of death?
      10. What was the manner of death? (homicide, suicide, accidental, natural, or unkown)
      11. What different characteristics of the skeletal bones help to identify it as human, age of skeleton, male/female, type of death? 

 

 

Female

Male

Cranium 

medium to large in size

large in size

forehead

high in height, vaulted, rounded

low in height, sloped, backward

brow bone

diminished

pronounced

mastoid process

diminished or absent

pronounced

mandible angle

obtuse (>90 deg)

approx. right angle (90 deg)

pelvis opening

wide, circular

narrow, non circular, heart shaped

sacrum

short, wide, turned outward

approx. equal width/length, turned inward

subpublic angle

approx. right (90 deg)

acute (<90)

femur

narrow, angled inward from pelvis

thick, relatively straight from pelvic

overall skeleton

slender

robust

age (months)

closure

6-9

mandible fused

4-6

humorous head bone fuse

7-8

pelvis frontal bones fuse

4-16

femur shaft sections built

9-13

elbow bones fuse

10

finger bones fuse

16-18

femur head fused to shaft

18

Wrist bones fused

18-21

Humeral head bone fused to shaft

18-24

Sternum fused to clavicle 

20-25

Pelvic bones fully formed

21-22

Clavicle fused

21-30

Lambdoidal suture fused (back of head) 

24-30

Sacrum bones fused 

30-32

Sagittal suture (centre of cranium) fused

48-50

Coronal suture (front of cranium) fused
 

Eye orbitals

Nasal cavity 

incisors

Cranium frontal plane

Caucasoid 

oval

Long, narrow

smooth

flat

mongoloid

circular

small , rounded

Shovelled interior

Flat or projected outward

negroid

square

wie

smooth

Projected outward

 

 

Caucasoid (all measurements in centimetres)

Negroid (all measurements in cm)

Unknown (all measurements in cm)

Female

Height = femur length x 2.47+54.10

height=femur length x 2.28 + 59.76

Height= femur length x 3.01 + 32.52
 

Height = humerus length x 3.36 + 65.53

height= humorous length x 3.08 + 64.67

Height= humorous height x 4.62 + 19.00

Male

height= femur x 2.32 + 65.53

Height = femur x 2.10 + 72.22 

height= femur x 2.71 + 45.86
 

height= humorous x 2.89 + 78.10

height= humerus length x 2.88 + 75.48

height=  humerus x 4.62 + 19.00

 

  1. Role of forensic entomologist- study of insects and their relation to criminal investigation, used to estimate time of death
    1. By determining the oldest stage of fly found on body, entomologist can approximate the postmortem interval
    2. Most common and important is the blowfly- green or blue
    3. After decomposition necrophagous insects descend on body within 24 hours depending on environment
    4. Typically a blow fly can lay 2,000 eggs-laid in human remains and hatch into maggots which eat human tissues and organs
    5. Can determine approximate time for how long a body has been left exposed by examining stages of fly larvae
    6. Time required for fly stage development is affected by location, climate, weather, and drugs
    7. Some beetles show up to eat blowflies, as body dries omnivorous insects feed on body and nearby vegetation (ants and wasps) spiders are the last to show up
    8. Other contributions
      1. Evidence should be collected by forensic entomology expert who takes temperature readings and take specimens from every area
      2. First arriving insects like moist warm open wounds, most insects found on body will likely ingest any drugs in the system and be good evidence
      3. If insects found extensively on hands and arms indicates defensive wounds
  2. George zimmerman case: self defence or murder

 

  1. Questions:
    1. Who was trayvon martin
      1. Trayvon martin was a 17 year old boy who was victim to a murder
    2. Who is george zimmerman
      1. George Zimmerman was a 38 year old neighbourhood patrol who killed Trayvon 
    3. What are the details of that night that ended with the death of trayvon
      1. Zimmermann was on his way to the target  when he noticed Travon walking slowly down the street looking at houses. George called the police to report him while following him. Trayvon thought he was being creepily followed, so he began to run to “escape”.The police dispatcher told Zimmerman to meet a policeman by the mailboxes. When he arrived, he got out of his car and Travon was hiding between bushes and attacked him. . Trayvon was pinned to the ground and he reached up to shove Zimmermann off him. Zimmermann was armed, so he believed that the boy was trying to grab the gun to shoot him. Zimmermann shoved Trayvon to the ground, grabbed his gun, and shot him. 
    4. Why did the police dispatcher tell zimmerman not to follow trayvon and why was that not considered an order
      1. The police told Zimmerman to not follow him because he would be giving chase. It was not considered an order because it was more of a suggestion, they said they didn’t need him to do that, instead of do not do that. 
    5. What evidence leads one to believe zimmerman’s side of the story and not that that the events of that night happened the other way around with words on top of trayvon
      1. The distance of the gun is consistent in zimmerman’s story
      2. Photos of zimmerman’s wounds prove he was trying to defend himself
      3. Gunpowder was found on trayvon’s chest, supporting zimmerman’s claim that they were on top of each other when he killed the boy
    6. Was it wise for the prosecution to not make this about race? Why do you think so? 
      1. I think it was wise, Zimmerman’s self defence was not racially motivated. The case had very little to do with race. 
    7. Why did Rachel Jentel not end up being the state’s war witness? What about her testimony made jurors feel uncomfortable and not help endure her to their hearts
      1. She had difficulty with literacy and speaking. SHe also lied to the court claiming that she didn’t want to talk about Trayvon because she was the last person he talked to. 
    8. Who gave the defence their best testimony and what was it about
      1. Jon Good gave the best testimony because he saw the fight. He testified that Martin was on top of zimmermann and that zimmerman was the one calling for help. 
    9. What evidence does lisa bloom give for the prosecution’s half hearted attempt and inability to win what she thinks is a winnable cas
      1. She says that Trayvon could not have seen the gun and would have needed X-ray vision. In several accounts, Zimmerman’s shirt came up and it was very easy to see the gun behind his back. She also claimed that this “murder” was racially motivated. 
  2. Harold shipman, aka Dr. Death
    1. What kind of doctor was Shipman
      1. He was a general practitioner
    2. Did Dr shipman ever lose his licence to practise medicine prior to being arrested
      1.  
    3. What was the name of the last victim that ended up being his demise
      1. Kathleen Grundy
    4. How did dr shipman finally get caught
      1. Morphine was found in Kathleen’s body 
    5. What year is most likely the first time that he killed his patients
      1. 1975
    6. What are the 3 predominating theories about why Dr Shipman killed his patients?
      1. Seeking to avenge the death of his mother
      2. He was addicted to killing
      3. He was practising euthenasia 
    7. How did Dr shipman avoid being caught sooner than the death of kathleen grundy
      1. He would kill old women who were most likely going to die soon, and blame it on old age
    8. How many and what convictions did shipman receive 
      1. He was convicted of murdering 15 of patients under his care
    9. What evidence was presented at his trial by the prosecution
      1. Kathleen’s will was forged with no acknowledgment to her children
      2. Kathleen’s body was exhumed and morphine was found in her body
      3. Shipman was the last person to see her alive
    10. where is dr shipman today
      1. He commited suicide in August, 2022

Ch 5: properties of matter and glass

 

  1. Physical vs chemical properties
    1. Physical properties such as weight, volume, colour, boiling paint, and melting point describe a substance without any reference to any other substance
  2. Chemical property:
    1. Describes the behaviour of a substance when it reacts or combines with another substance
  3. Measurement system
    1. Scientists used metric system except usa
    2. Metric- metre, gram, and litre
    3. 1 inch- 2.54 cm
    4. 1 lb-453.6 g
    5. 1 L- 1,06 qt
      1. Deci = 1/10 or 0.1
      2. Centi = 1/100 or 0.01
      3. mili  = 1/100 or 0.001
      4. Micro = 1/1000000 or 0.000001
      5. Nano = 1/1000000000 or 0.000000001
      6. Kilo = 1,000
      7. Mega = 1,000,000
  4. Nature of matter
    1. element= simplest substance known and provides the building blok rom which all matter is composed
      1. All elements are in periodic table
    2. Two or more elements form a compound
    3. Atom is basic particle of an element and matter is smallest unit of compound
    4. Matter is anything that has a mass and occupies space
  5. States of matter
    1. Solid
    2. Liquid
    3. gas/vapour
    4. Substances can change from one phase to another without forming a new chemical species
    5. Sublimation- substance goes from solid straight to gas (dry ice) 
  6. Theory of light
    1. Two models describe behaviour of light
      1. Light is described as wave of light, continuous wave
      2. Stream of discrete energy particles
      3. When white light passes through prism, it is dispersed into continuous spectrum of colours
      4. Visible light ranges in colour from red to violet in electromagnetic spectrum
      5. Wavelength: ds=istance bet two successive crests (or troughs) measured in nanometre
      6. Frequency: number of crests (or troughs) passing any one given point per unit of time- cycles per second  cps
      7. Frequency and wavelength are inversely proportional to each other F=C/wavelength
      8. Electromagnetic spectrum is entire range of radiation energy from most energetic cosmic rays to least energetic radio waves
      9. Visible light is only small part of electromagnetic spectrum
      10. Wavelength and frequency are inversely proportional 
  7. Light as a wave
    1. Dispersion: process of separating light into its component colours when you pass light through prism it slows the different wavelengths down causing it to exit the prism as respective colours
    2. Refraction” bending of light waves because of a change in velocity
      1. Such as when light passes through glass
    3. Electromagnetic radiation moves through space, its behaviour can be described as continuous wave
    4. Once radiation absorbed by substance, discrete particles of light known as photons
    5. Helps forensic scientists as they determine what substance is by the type and quantity of light it absorbs 
  8. Important physical properties
    1. Temperature is a measure of heat intensity
      1. Most commonly used temperature is celsius scale
      2. Celsius is derived by assigning freezing point of water at 0 and its boiling at 100
  9. Temperature scale
    1. Farhenheit is based of freezing point of 32 and boiling point is 212, difference between two is 180 units
    2. Celsius is 1/100 of the temperature change between the two points
    3. Weight: the force with which gravity attracts a body
    4. W=mg (g=gravity)
    5. Mass: amount of matter an object contains independent of gravity- when you go to the moon your weight changes but your mass is the same
    6. Mass of an object is determined by comparison to the known mass of standard objects
    7. Density defined as the mass per unit volume: D=M/V
    8. Density is intensive property of matter- remains same regardless of sample size
    9. Density considered a property of a substance and can be used as aid in identification
    10. volume can be calculated by placing it on cylinder of a known body of water (V1) and then measuring the new volume (V2) and then subtracting the difference (V2-V1) to fund density
    11. Light waves travel in air at constant velocity until they penetrate another medium at which point they are suddenly slowed,d causing waves to bend
    12. Bending of light waves bc of a change in velocity- refraction
    13. Refractive index is the ratio of the velocity of a light in a vacuum to that in the medium under examination
    14. 25 celsius the refractive index of water is 1.333- means that light travel 1.333 times faster in vacuum than water
    15. Refractive index is an intensive property and will serve to characterise a substance
    16. Crystalline solids have definite geometric forms bc of the orderly arrangement of atoms
    17. These solids refract beam of light in two different light ray components
    18. Results in double refraction
    19. Birefringence is numerical difference between two refractive indices
    20. Not all solids are crystalline in nature- glass has random arrangement to dorm amorphous (non crystalline) solid

 

  1. Glass fragment
    1. Glass is hard, briuttle, amorphous substance composed of silicon oxides mixed with various metal oxides
    2. Amorphous solids have their atoms arranged randomly unlike crystals
    3. Tempered glass is stronger than normal glass due to rapid heating and cooling
    4. Laminated glass is found in car windshield has a layer of plastic between two pieces of window glass
    5. For forensic scientist problem of glass comparison is one that depends on the need to find and measure those properties that will associate one glass fragment with another while minimising or eliminating other sources 
    6. To compare glass fragments a forensic scientist evaluates two important physical properties: density and refractive index
  2. Floatation method
    1. Precise and rapid method for comparing glass density
    2. A glass particle is immersed in liquids
    3. Density of liquid is carefully adjusted by the addition of small amounts of appropriate liquid until glass chip remains suspended in liquid
    4. At this point glass will have same density as liquid and can be compared to relative pieces of glass
  3. Immersion method
    1. Flotation and immersion are best used to determine a glass fragments density and refractive index
    2. Latter involves immersing a glass particle in a liquid medium whose refractive index is varied until it is equal to that of a glass particle
    3. At this point, known as match point, the becke line disappears and minimum contrast between liquid and particle is observed
    4. Becke line is a bright halo near the border of a particle that is immersed in a liquid of a different refractive index
    5.  

 

  1. Analysing cracks 
    1. [penetration of window glass by projectile produces cracks which radiate outward (radial fractures) and encircle the hole (concentric factore)
    2. By analysing the radial concentric fracture patterns in glass the forensic scientist can determine direction of impact
    3. High velocity projectile such as bullet leaves hole that is wider at exit side and hence its examination is important when determining the direction of impact
    4. Direction of impact can be accomplished by applying 3R rule: radial cracks form right angle on the reverse side of force
    5. Sequence Of impacts when there have been successive penetrations of glass is frequently possible to determine because the fracture always terminated art an existing line fracture
  2. Collection of glass
    1. In the remotest possibility exists that glass fragments may be pierced together, every effort must be made to collect all glass found
    2. When an individual fit is though improbably, the evidence collector must submit all glass evidence found in the possession of the suspect along with a representative sample of broken glass remaining at the crime scene
    3. glass fragments should be packaged in solid containers to prevent further damage
    4. Isf suspects shoes or clothing are examined for glass fragments, they should be individually wrapped in paper and transmitted to laboratory
    5.  
  3. Charles Lindbergh baby kidnapping:
    1. https://www.fbi.gov/history/famous-cases/lindbergh-kidnapping
    2. Who was charles?
    3. Who were the suspects
    4. Who all “helped” in trying to recover the child
    5. What ransom was paid
    6. How was the suspect caught
    7. What evidence was used to convict

Ch 5.5: Polarising microscopy: 

 

Ch. 6: Drugs 

 

Ch. 9: Forensic serology

Blood type

Antigen on RBCs

Antibodies in serum

A

A

anti-B

B

B

anti-A

AB

AB

Neither anti A nor B

O

none

Both anti A

https://www.humbleisd.net/cms/lib2/TX01001414/Centricity/Domain/3959/blood%20typeKEY2015.docx

 

Ch. 10: DNA: the indispensable forensics science tool

 

Ch. 11: Blood Splatter

Ch 12: Trace evidence I- hairs and fibres

The most common request is to determine whether or not hair recovered at crime scene compares to hair removed from suspect

 

4pCh 13: metals paint and soil

;

Ch.14: forensic aspects of fire investigation

Ch 15: forensic investigation of explosion 

Ch 15: fingerprinting