Physical Evidence 1
What are the 3 R's of physical evidence?
1) Recognize, 2) Record, 3) Recover
True or False: Lineup fillers need to be only the same race as the suspect.
false, there are many factors besides just race to consider.
Explain why concerns about transmittable diseases like AIDS or HepC need to be addressed by investigative agencies.
if investigators do not feel safe while collecting evidence (for example, they don't feel latex gloves are fully protecting them from contact) then they may cut the investigation short/hurry the process or avoid collecting crucial pieces of evidence.
Explain the weapon focus effect.
the concept that having a weapon present during the commission of the crime makes the witness focus on the weapon instead of the perpetrator's facial details, making the possibility of an accurate identification less likely due to weakened memory/attention
True or False: Evidence is processed at local labs because of the concern for the chain of custody if evidence were to be shipped by UPS to a different location.
false - receipts for transportation through UPS can be included in the chain of custody without concern to the validity of the evidence.
What responsibility trumps all other responsibilities for the first responding police officer to the scene of the crime?
medical aid for the injured
Explain the difference between a composite and a sketch
a composite is a computerized program where the witness looks at several versions of individual features (nose, eyes, brows, etc.) and puts the selected versions together to create a face. A sketch is done with a police artist who has the witness describe the face as he/she draws in the details.
Demonstrate the pharmacists fold with a piece of paper and a paper clip
folding in 1/3rd from both directions until a small package is created with no open sides.
What are the 3 phases that, when combined, make up your memory?
Encoding, Storage, Retrieval
What are the 4 ways to record the crime scene?
1) notes, 2) videos, 3) photos, 4) sketches
What is the name of the currently used analysis that provides a DNA profile?
Short Tandem-Repeat (STR) analysis
What is a Rogue Gallery and who has a great deal of discretion in connection to the use of a rogue gallery?
the filing system of mugshots which witnesses can look through when making an identification. The file administrator has great power in choosing which photos to include in the rogue gallery shown to a witness and ultimately determines (without knowing so) whether he/she is presenting a target present or target absent group.
Define whole substrate collection
taking the entire object back to the lab for further processing
Explain the difference between relative judgment and absolute judgment in lineup selection decisions.
relative judgments occur when witnesses select the person who looks MOST like the perpetrator RELATIVE to the other members of the lineup (common in simultaneous lineups) whereas absolute judgments occur when witnesses select a person only if the features line up with their MEMORY of the perpetrator (more likely in sequential lineups)
Name 1 of the 3 ways to measure distance in a crime scene sketch.
Triangulation, Polar Coordinates, or Base Line
Name and explain the 3 types of fingerprints that can be left behind at the crime scene.
1) Plastic, which are left in soft material and create a 3D print, 2) Patent, which are left after contact with some kind of colored material, and 3) Latent, which are left from natural sources which cannot be seen without processing.
Explain the 2x2 box options that could occur in any eyewitness identification procedure (you can draw it out if that helps). Which of these are correct vs. incorrect?
you could make a choice or not, and it could be a target present or target absent lineup. Those together as columns and rows create 4 options: choosing in a target present lineup and not choosing in a target absent lineup are CORRECT. Choosing in a target absent lineup and not choosing in a target present lineup are INCORRECT.
Blood with A antigens in the red blood cells and B antigens in the plasma and no presence of the Rh factor is known as what type of blood?
A-
Explain the difference between an identification parade, a photo array, and a show-up. Which is the best option to conduct, if possible?
a live lineup conducted in front of the witness with at least 6 members from which they will choose 1 person (this is best if possible), a photographic display of at least 6 members presented to the suspect from which they will choose 1 person, a single person (the suspect) presented in either live or photo form to the suspect to indicate yes or no to.
What kind of chemical evidence allows investigators to determine how far the muzzle of a weapon is to the target they have hit?
gunshot residue
What's the difference between a checkerboard search and a lane search?
a checkerboard is split into small squares by creating parallel rows and columns through the entire scene and focusing only on each small square before moving on to the next. A Lane search splits the scene into rows OR columns and focuses on finding evidence within that lane before moving on to the next (or having a difference person process each lane).
Explain what the double blind testing procedure means in an eyewitness identification situation.
the lineup administrator does not know which member of the lineup the suspect is therefore cannot influence the witness's decision through conscious or unconscious bias/feedback. This is called a DOUBLE blind procedure because both the administrator and the witness do not know - if the witness did not but the administrator DID know, that would be a single blind procedure.
What are the 3 types of primary classifications seen in fingerprints? Which is most common? What is one secondary classification?
Loops, Arches, and Whorls. Loops are most common in approximately 66% of the population. Bifurcation, ridge ending, dot, island, hook, bridge, ridge crossing, etc are all examples of minutiae identified in the secondary classification process
Explain the difference between system and estimator variables, and give 2 examples of each
System are controllable factors (such as filler similarity, lineup instructions, simultaneous vs. sequential presentation, etc.) whereas Estimator variables are those that are not controllable by the CJ system (such as cross race effect, weapon focus effect, distance/lighting/length of time/view, level of stress/arousal, etc.)
Daily Double! Explain the difference between individual and class characteristics. Which one creates an identity vs. an identification?
class characteristics (like blood type) is group level information which allows an identity to be created, whereas individual characteristics (such as a DNA sample) allow you to classify down to a group of only 1 person thereby creating an identification