CODIS Flashcards
1
Q
what does it mean when a profile is attributable to putative perpetrator
A
- is the profile attributable for a putative perpetrator?
- DNA profiles from forensic evidence submitted to NDIS can only contain alleles that are potentially attributable to the putative perpetrator(s)
- shared alleles can be uploaded
- if the answer is no, the profile is not allowed in CODIS
- not all probative profiles are eligible to NDIS
- the victim’s profile on the suspect’s clothing is not eligible for CODIS
2
Q
what is the autosearcher
A
- newly entered profiles are searched against SDIS nightly
- once profiles are marked for upload into NDIS (after admin review), they are automatically searched every weekday
3
Q
explain CODIS eligiblity
A
- is there documentation to indicate that a crime was committed
- was the profile developed from biological material from crime scene evidence
- is the profile attributable for a putative perpeetrator
- is there a suspect in the case
- was the item seized by law enforcement from the suspect’s peron, or was it in possession of the suspect when collected
- eligibility must be determined and SP# must be tech-reviewed before being searched
4
Q
describe the CODIS unit workflow
A
- prep samples, lyse, amplify, capillary electrophoresis, review
- for “dirty amp”
5
Q
what is the combined DNA index system (CODIS)
A
- US national DNA database that is maintained by the Federal Bureau of Investigation (FBI)
- there are twenty CODIS core STR loci required for upload of DNA profiles into the national DNA database
- hierarchal levels
- NDIS (national)
- SDIS (state)
- LDIS (local)
6
Q
describe direct amplification
A
- method of amplification without performing isolation and purification
- directly amp blood and buccal samples
7
Q
what is DISC
A
- DNA Index of Special Concern
- virtual index of forensic unknowns that meet certain eligibility criteria
- used as the arrestee rapid DNA database
- the only profiles arrestees are searched against during booking
- arrestee samples will be searched against all of CODIS during the next SDIS autosearch
8
Q
what are the DISC eligibility requirements
A
- case type: homicide, sexual assault, kidnapping, terrorism
- specimen category: forensic unknown
- completeness: complete at original 13 CODIS core loci
- source ID: must be an unknown profile (source ID = no)
- metadata: must have required casework metadata
9
Q
describe the required documentation for CODIS eligibility
A
- is there documentation to indicate that a crime was committed?
- an analyst must review the details that are available in the case documentation
- not everything submitted to the lab may be crime scene evidence
- ex: suspect puts out a cigarette in an ashtray in a restaurant
- if the answer is no, the profile is not allowed in CODIS
10
Q
what is a DVOVC
A
- deceased victim of violent crime
- searched at SDIS only
- allows victim references to be uploaded to SDIS if they die as a result of a specific crime of violence
- homicide, battery, kidnapping, arson, robbery, terrorism, etc
- sexual assault victims do not go into CODIS
11
Q
explain follow-ups for CODIS hits
A
- we request timely notification of the state of outstanding CODIS h its
- active case, cold case, can’t find offender, etc
- if there are hits to individuals other than the perpetrator, they must be removed from CODIS asap
- outstanding CODIS hits are emailed to agencies monthly
12
Q
requirements of the forensic mixture index
A
- specimen category: forensic mixture
- completeness: 8 original core loci
- requirements: no more than 4 alleles at any locus, >3 alleles at two or more loci, an MME of 1 in 10 million
13
Q
requirements of the forensic partial index
A
- specimen category: forensic partial
- completeness: 8 original core loci
- requirements: single source or fully deduced mixture, incomplete, dropout at any of the original 13 core loci, 1 locus with up to 3 alleles and all remaining loci with up to 2 alleles, MME greater than 1 in 10 million
14
Q
requirements of the forensic targeted index
A
- specimen category: forensic targeted
- completeness: 8 original core loci
- requirements: forensic partial or forensic mixture that has an MME less than 1 in 10 million, and an MRE greater than 1 in 10 million
- if more than 10 hits are generated, remove from CODIS
15
Q
requirements for the forensic index
A
- specimen category: forensic unknown
- completeness: 13 original core loci
- requirements: single source or fully deduced mixture, complete, 1 locus with up to 3 alleles and all remaining loci with up to 2 alleles
16
Q
explain high stringency
A
- the number of alleles in the target locus must be the same as the number of alleles in the candidate locus
- ex:
- target locus: 12, 14
- candidate locus: 12, 14
17
Q
what is a hit confirmation
A
- CODIS hit notification letters are released to the casework lab or submitting agency
- admin-reviewed before release
- gives agencies probable cause to get a warrant for a reference sample, but does not give probable cause for arrest
- lawfully-owed arrestee, convicted offender, or legal specimens cannot be used as reference samples in forensic cases
18
Q
how does the way an item was seized relate to CODIS eligibility
A
- was the item seized by law enforcement from the suspect’s person, or was the item in the possession of the suspect when collected by law enforcement?
- if the suspect’s profile is reasonably expected to be on an item at the crime scene, then it is not a forensic unknown
- it is considered a suspect reference and is not allowable at NDIS
- if the answer is yes, the profile is not allowed in CODIS
- if the answer is no, the profile is allowable in CODIS
19
Q
explain low stringency
A
- at least one of the alleles in the target locus match one of the alleles in the candidate locus
- ex:
- target locus: 10, 11
- candidate locus: 10, 12
- ex:
