Investigations Flashcards
What two phases are investigations divided into?
The primary phase includes the immediate actions described as ‘the golden hour tasks’, such as initial scene examination, witness management, capturing forensic or communications evidence and dealing with urgent arrests.
The secondary phase continues (often with a ‘handover note’ if there is an arrest, or in any case, a basic initial crime report) into the meticulous building of a case, e.g. through interviewing and preparation of evidential files all the way through to court.
What are the key building blocks to all investigations?
Preserve life
Preserve scene
Secure evidence
Identify suspects
Identify victims/ witnesses
Early consideration should be given to Golden Hour Actions based on the situation that presents itself, concentrating on evidence that would be lost unless immediate action is taken. These actions may include:
Giving concise updates on the situation and seek additional and specialist support,
Identifying if a cordon, and a common approach pathway is required,
Identifying suspects, and deciding if arrest is necessary (e.g. will we lose track of them, or do we need to immediately secure forensic samples from any suspects?),
Maximising the use of bodycam evidence and properly record any significant comments,
Developing intelligence opportunities, such as requesting control room intelligence checks on suspects to find known addresses and associates,
Immediate seizure and protection of evidence from loss, or damage by the weather,
Identifying electronic evidence - identify passive data opportunities that may be lost e.g. routers and mobile phones,
Initiating witness searches, identification and secure initial key statements and support,
Beginning to identify possible motives and explanations,
initial thorough crime scene assessment and forensic examination (often by Crime Scene Examiners, sometimes also known as Scene Of Crime Officers or SOCO) – including any blood pattern analysis, prints and chemical analysis,
Immediate media management and notifying relevant supervisors and senior officers to ensure the appropriate resources are released to support a thorough investigation.
Above all else PRESERVE LIFE!
What is Locard’s Theory?
Forensic scientist who formulated the basic principle of forensic science “every contact leaves a trace”.
When we are investigating a crime, this could mean any contact that a suspect, victim or witness has with one another, or indeed with any other thing (such as a vehicle, furniture, weapon or phone), which results in the exchange of material (such as fibres, shoe marks, glass fragments, fingerprints, blood, semen, firearm discharge residue, DNA, and so on).
The contact doesn’t have to be substantial or sustained and could be fleeting or even passive e.g. splattering of blood on a wall from an impact some distance away.
In simple terms, the principle of crime scene management is to:
Preserve a scene and keep it exactly as it was when the crime occurred,
Minimise contamination, and
Forensically examine the scene (which may contain
physical and electronic evidence that needs preserving and harvesting).
Top Tips: Prevent Scene Contamination by:
Having plastic gloves and a face mask ready; while on frontline duty, ALWAYS carry with you half a dozen pairs of gloves,
Treating forensic sampling as a priority,
Never dealing with evidence from two facets of the same crime (i.e. suspect and victim),
Transporting victim and suspect in separate vehicles until forensic sampling is completed,
Cleaning and inspecting your patrol car daily.
Forensics in the scientific process demands:
Unbroken continuity of evidence,
Correct packaging with integrity seals,
Great care in preventing contamination,
Clear communication about the investigation details,
Guidance regarding points to prove, updates and time deadlines.
Exhibit Handling
Paper bags should be used for…
bedding, fabric, shoes and clothes which allow them to breathe and prevents mould and bacteria developing.
The top of the bag must be folded over twice and sealed with tape that allows the officer to seal it with their identification.
Exhibit Handling
Wet or damp items (including with blood) need to be…
dried (and not folded if it is blood to allow for blood pattern analysis) and a health hazard sign placed on the item.
Exhibit Handling
Polythene bags should be…
tamper proof bags, but if not, a signature seal should be used.
Exhibit Handling
Nylon bags (used to store hydrocarbons and flammable substances) should be…
twisted into a “swan neck” and secured with tape and a cable tie.
The sealed nylon bag should then be sealed in a polythene bag and again “swan necked” and then placed in a signature sealed and exhibited, rigid container and kept away from other items.
Exhibit Handling
Sharps, bladed weapons, screw drivers and other pointed objects are…
a health hazard and specialist tubs and exhibit boxes should be used.
Needles should be discarded in a sharps box prior to packaging a syringe with great care.
Exhibit Handling
Firearms are…
a serious hazard risk and you should seek immediate firearms/CSI support.
Firearms with forensic interest, after being made safe, place in a sealed box with a safety certificate.
Exhibit Handling
Bottles and glasses can be…
immobilised in a box to preserve fingerprints and DNA.
Exhibit Handling
Urine samples…
use specialist kits and documents stored in stout card folders or boxes.
