ABMDI Decedent Identification Methods 2 — Questions and Answers
Question 1: DNA-based decedent identification requires collection of reference samples. Which of the following is an appropriate reference DNA source?
- A photo ID found at the scene
- A personal item with the decedent's DNA (toothbrush, razor) or a biological relative's DNA sample (Correct answer)
- The decedent's employment records
- An eyewitness identification
Correct answer: A personal item with the decedent's DNA (toothbrush, razor) or a biological relative's DNA sample
Reference DNA can be obtained from personal items bearing the individual's biological material, or via kinship analysis using samples from biological relatives.
In mass casualty events or decomposed remains cases, antemortem DNA profiles are established from personal items (toothbrush, razor, hairbrush) or from relatives (buccal swabs). These are compared to postmortem DNA profiles extracted from the decedent's remains. Both nuclear DNA and mitochondrial DNA may be used depending on sample quality.
Question 2: Dental identification is considered one of the most reliable methods because:
- Dental records are stored in national federal databases accessible to all MDIs
- Teeth are extremely durable, and unique dental patterns can persist through trauma, fire, and decomposition (Correct answer)
- Dental identification is required by law in all U.S. jurisdictions
- All people have identical numbers of teeth, simplifying comparison
Correct answer: Teeth are extremely durable, and unique dental patterns can persist through trauma, fire, and decomposition
Teeth are highly resistant to decomposition, fire, and trauma. The unique combination of dental restorations, missing teeth, and anatomical features makes dental comparison a highly reliable identification method.
Forensic odontologists compare postmortem dental radiographs and charting to antemortem dental records. Unique features include fillings, crowns, extractions, root morphology, and enamel patterns. Dental identification can be achieved even in severely decomposed or skeletonized remains.
Question 3: Which of the following identification methods is considered least reliable as a standalone identification?
- Fingerprint comparison
- Visual identification by a family member (Correct answer)
- DNA comparison
- Dental records comparison
Correct answer: Visual identification by a family member
Visual identification by family members is unreliable because grief, trauma, decomposition, or facial injuries can cause errors. It is not accepted as a primary scientific identification method.
Family visual identification is prone to errors, especially in cases involving decomposition, trauma, fire, or significant physical changes. Scientific identification methods (fingerprints, DNA, dental) are required for legal purposes. Visual identification may be used as a supplementary tool but most medicolegal systems require scientific confirmation.
Question 4: The term presumptive identification in death investigation means:
- The ME has signed the death certificate confirming identity
- Identity has been established to a high probability based on available circumstantial evidence but not scientifically confirmed (Correct answer)
- A fingerprint match has been obtained from AFIS
- Identity has been confirmed by DNA analysis
Correct answer: Identity has been established to a high probability based on available circumstantial evidence but not scientifically confirmed
Presumptive identification is a working identification based on strong circumstantial evidence (documents, belongings, visual) but not yet confirmed by scientific methods.
Presumptive identification may be based on driver's license, personal effects, next-of-kin statement, or visual recognition. It allows investigative and logistical processes to proceed while scientific confirmation is pending. Final identification requires scientific corroboration before the death certificate is issued.
Question 5: In mass fatality incidents, what system is commonly used to organize and track the reconciliation of postmortem and antemortem data?
- VICAP (Violent Criminal Apprehension Program)
- DMORT databases and reconciliation systems (Correct answer)
- NCIC (National Crime Information Center)
- ICE (Immigration and Customs Enforcement) databases
Correct answer: DMORT databases and reconciliation systems
In mass fatality events, DMORT (Disaster Mortuary Operational Response Teams) and associated databases are used to systematically reconcile postmortem findings with antemortem records for identification.
DMORT, under FEMA and the National Disaster Medical System, deploys to mass fatality incidents and uses standardized databases to track victims, postmortem data (DNA, dental, fingerprints), and antemortem records. The reconciliation process matches postmortem profiles to antemortem profiles to achieve positive identification.
Question 6: What is the primary use of the AFIS (Automated Fingerprint Identification System) in death investigation?
- Identifying living suspects at a crime scene
- Comparing postmortem fingerprints against national databases to identify unknown decedents (Correct answer)
- Storing fingerprints of deceased persons for future reference
- Verifying the identity of MDI personnel at secure scenes
Correct answer: Comparing postmortem fingerprints against national databases to identify unknown decedents
AFIS is used to compare fingerprints collected from an unknown decedent against existing databases to achieve positive identification.
MDIs or fingerprint specialists collect postmortem fingerprints and submit them to AFIS. The system compares ridge patterns against millions of stored records from prior arrests, immigration, military, and other government sources. A positive AFIS match provides scientific identification.
ABMDI Decedent Identification Methods 2
DNA-based decedent identification requires collection of reference samples.
Which of the following is an appropriate reference DNA source?