Science Flashcards
What 7 pieces of info go onto a CJA label?
Police force, exhibit number, description, address, date and time, name, signature
What MG is a witness statement
MG11
What 3 swabs do you take for blood?
Control, background, apparent blood swab
What 3 swabs do you take for saliva?
Control, wet, dry
What are contemporaneous notes?
Notes taken at the time of examination or soon thereafter
In what order would you collect exhibits? (3)
Photography, Forensic evidence, fingerprints/footwear
What exhibit number would photographs typically be in an examination?
Exhibit no.1
Penalty for possession of Class A drugs
7 years imprisonment, unlimited fine
Penalty for possession with intent to supply Class A drugs
up to life imprisonment, unlimited fine
Penalty for possession of Class B drugs
5 years imprisonment, unlimited fine
Penalty for possession with intent to supply Class B drugs
up to 14 years imprisonment, unlimited fine
Penalty for possession of Class C drugs
2 years imprisonment, unlimited fine
Penalty for possession with intent to supply Class C drugs
14 years imprisonment, unlimited fine
What class can prescription drugs be?
A, B and C
What is the name of the presumptive test for drugs?
Marquis
What is an SSM?
Scientific Support Manager
What is CBRN?
Chemical, Biological, Radiological, Nuclear
What is a SERM?
Scene Evidence Recovery Manager
What PPE are you expected to wear in an examination? (6)
Mask, Hood, Single and Double Gloves, Oversuit and Overshoes
What makes a burglary an aggravated burglary?
Weapon, Imitation firearm, Firearm, or Explosive
WIFE
Act for burglary
Theft act 1968 s.9
Act for aggravated burglary
Theft act 1968 s10
Sex offences act
Sex offenders act 2003
Presumptive test for semen
Acid Phosphatase (ACP)
How does ACP work?
Enzyme secreted by prostate gland detected
False positives by vaginal fluid
Persistence of seminal fluid in the mouth
Up to 48 hours
Persistence of seminal fluid in the vagina
24-72 hours, but occasionally up to 6 days
Persistence of seminal fluid in the anus
Until defecation but up to 3 days
Persistence of seminal fluid on the skin
Until washed away
Persistence of seminal fluid on clothing/bedding etc..
Indefinitely if kept dry/not washed
How to recover a condom?
Seal with freezer clip, place into close fitting rigid container, into scene bag and eventually frozen
What act does fire come under?
Criminal Damage Act 1971
Recovering exhibits believed to have accelerant on?
Nylon bag in a nylon bag. If liquid, decant into container then place nylon bag on top before lid.
What is Flashover?
The point at which all near combustible material ignites
What is Backdraft?
When oxygen is reintroduced to a starving fire
What can Nylon Bags be contaminated by?
Hydrocarbons from vehicles (fuel). Can produce false positives.
Describe human behaviour in fires and what this can lead to
Confused and Disorientated - bodies can be found in unexpected places.
How to recover wet clothing from fire scenes?
Nylon bag - do not dry
What is the rule of 9s and what does it refer to?
Estimates size of burn and a burn’s percentage of total skin / chance of recovery (60%-80% burned - little chance of recovery)
Sample types and comparison methods (4)
Questioned sample
Positive control
Negative Control
Reference Collections
What 4 types of evidence need to be recovered immediately
GSR
Blood
Fibres
Trace
What is an IED?
Improvised Explosive Device
5 Components which make up an IED
Power Supply
Initiator/detonator
Explosive
Switch
Container
Features of a Primary explosive?
Highly sensitive, impact, friction, heat. Used in detonators.
Features of a Secondary explosive?
Not as sensitive as primary; safer to handle; TNT
Household products used in IEDs (4)
Fertilizer
Weed Killer
Solvents (acetone)
Hair colouring Dye
What is EOD
Explosive Ordnance Disposal (bomb squad)
How do EOD detonate a bomb?
Target the battery to disrupt the power supply
What is FEL?
Forensic Explosive Laboratories (only place all explosive evidence can go to)
What is a TERK?
Trace Evidence Recovery Kit
3 Types of exhibits from explosive scenes
Explosive materials
Non explosive debris (nuts/bolts etc)
Bulk non explosive debris (sweepings/ clothing etc)
Role of first officer attending at major incident (5)
Confirm situation
Secure area
Cordon area
Control access
Call for CSI
3 things that is done at the post mortem
Toxicology
Samples of Organ Tissue (histology)
Blood and pre-transfusion sample from hospital
2 types of death
Somatic death (no sentient personality)
Cellular death (tissues/cells dead from cardio-respiratory failure)
What is Pallor Mortis?
Pale-ing of skin
What is Algor Mortis?
Cooling of body after death
What is Livor Mortis? (hypostasis/lividity)
Pooling of blood to the lowest extremities
What is Rigor Mortis?
Stiffening of body (disappears after 24-36 hours)
How long does Livor Mortis take?
Fully developed between 3-4 hours, fixed after 16 hours, can look like bruising.
What is putrefaction?
Decomposition/autoloysis. Begins 2-3 days after death
What happens 2-3 weeks after death?
Organs and cavities bursting
What happens 3-4 weeks after death?
Liquefaction of soft tissue, degloved, face unrecognisable
What happens 4-6 months after death?
Formation of adipocere (mortuary wax)
What forensic evidence can you get from mummified bodies?
DNA, fingerprints
What can be determined from skeletonization?
Age and gender
What kind of deaths do coroners investigate?
Unknown deaths,
Violent or unnatural deaths,
Deaths in police custody, prison, or another type of state detention
What is required to become a coroner?
Either a medical or legal background
What teams may be needed to recover a body in water? (4)
CSI, Fire service, Under water search team, lifeboat crew
What 3 things can link an offender to a water scene?
Clothing, weapons, diatoms
How to tell if a victim drowned or was deceased before entering a body of water
Diatoms will be found circulated around organs if water is inhaled.
What is Limnology?
Analysis of evidence collected from crime scenes in or around fresh water sources
Strategy for major incident investigations? PPAR
Preserve
Protect
Asssess
Record
What is the first insect to attack a body after death?
Blow fly -turn into maggots
What can impact PMI?
Ambient temperature
Central heating
Climate
Clothing
Body mass/core temp
Time
3 different types of death
Murder
Suicide
Natural causes
What kind of pm does each type of death get?
Murder - home office with advanced photography
Suicide - local with photography
Natural causes - no csi needed
What is a coroner?
Independent judicial office holder appointed by a local authority within the coroner area
Can a coroner attend a scene?
Rarely, but may attend a mass fatality
What can affect evidential opportunities for water scenes?
Persistence
Adipocere
Washing
Temperature
Tidal flow
Abrasive sand or river bottom
What do you take the temperature of at a water scene?
The body of water itself
The body if one is present
What is a diatom?
Photosynthesising algae
What do you take a control of at a water scene?
Control sample of diatoms - frozen
(Found in almost every source of water)
What is the standard body recovery process? (10 steps)
Photography
Trace evidence
Tape lift exposed skin
Hair combing
Swab hands and nail clippings
Swab exposed skin
Bag hands/feet/head
Place body onto body sheet
Remove clothing
Wrap body
What to consider when recovering a decomposed body?
Skin slippage
Leakage and degradation
What is the NCA?
National Crime Agency
What is a postmortem?
Examination of a body after death
Where is a body taken after a violent crime has occurred?
Home office postmortem
Why are postmortems needed?
Unknown cause of death
Unnatural or violent cause of death
Death in police custody/prisons
Unknown identity
Determine whether inquest is neededd
2 types of post mortems
Home office postmortem
Hospital post mortem
(Coroner must be informed of either)
Health and safety regarding mortuary’s
Designated gowning and de gowning areas
Hep B, tuberculosis and HIV - main diseases to be aware of
What swabs are taken of a deceased person?
Orifice swabs (mouth, nasal, vaginal, penile, anal)
Injury site swabs
Extraneous materials swabbed
Scientific Support Services (9)
CSI Unit
Forensic Investigation Unit
Forensic Imaging Unit
Fingerprint Identification Services
Fingerprint Enhancement Lab
Digital Investigation Unit
Footwear Unit
Pathologists
Firearms
What to remember when recovering body fluids?
Biohazard tape
Major Incidents (8)
Murder (attempted)
Serious Assault
Serious Arson
Rape
Mass Disaster
Kidnapping
Serious Firearms Incident
Terrorism
Order of mortis
Pallor, Algor, Livor, Rigor
When is Livor Mortis fixed?
16 hours
When does rigor mortis disappear?
After 24-36 hours
When is Livor Mortis fully developed?
3-4 Hours
How long does Algor Mortis take?
About 18-20 hours to match outside temperature
How long does Pallor Mortis take?
Can take 15-30 minutes to begin
How long does GSR last on hands?
2-4 hours
How long does GSR last on face and hair?
6-12 hours
How long does GSR last on clothing surface?
Up to 24 hours if worn