General Knowledge Flashcards
(47 cards)
What does LEVA stand for?
Law Enforcement and Emergency Services Video Association
What does DAIS stand for?
Digital Automotive Image System
What is a Touhy Letter
A written request for official information from a government agency for use in litigation. It is required when a federal employee is to testify in a non-federal trial.
The Touhy request is named after the 1951 Supreme Court case Touhy v. Ragen.
What is a hash?
A unique, fixed-length string of characters generated by a mathematical function called a “hash function” that takes any input data (such as a text, file, or password) and converts it into a shorter, seemingly random string, ensuring that even the slightest change in the original data will result in a completely different hash.
In our reporting, we provide the hash of the original product and the hash of the final product.
How is overall resolution calculated?
Vertical pixels x horizontal pixels
What is aspect ratio?
The relationship between height and width
What is the standard HD resolution? What is its aspect ratio?
1920 x 1080
16:9
Describe 1993 Daubert v Merrell Dow Pharmaceuticals?
It is the case that established the Daubert Standard for evaluating scientific evidence in court. The case involved a claim that the morning sickness drug Bendectin caused birth defects.
The plantiffs were children born with birth defects and their parents. They alleged that Bendectin caused the defects.
The trial court dismissed the case, finding that the plaintiffs’ scientific experts’ testimony was inadmissible.
The Supreme Court ruled that the Federal Rules of Evidence do not require scientific evidence to be “generally accepted” to be admissible.
The Daubert Standard requires judges to act as gatekeepers of scientific evidence. Judges are responsible for:
Ensuring that the expert testimony is relevant
Ensuring that expert testimony is based on a reliable foundation
Scrutinizing the expert’s methodology and reasoning
The Daubert Standard aims to reduce the admission of unreliable of pseudoscientific expert testimony.
What are the 5 Daubert Standards/Factors?
Testability: Whether the theory or technique has been or can be tested
Peer review: Whether the theory or technique has been reviewed and published by other experts
Error Rate: The known or potential rate of error for the theory or technique
Standards: Whether there are standards or controls in place for the theory or technique
Acceptance: Whether the theory or technique is widely accepted in the relevant scientific community.
Describe the 1923 Frye case
A court case that established the Frye Standard, which determines if scientific evidence can be admitted in court. The case involved the admissibility of a systolic blood pressure lie detector test (polygraph) as evidence.
The court ruled that the polygraph was not admissible because it lacked general acceptance in the scientific community.
The court established that an expert opinion is admissible if the scientific technique on which the opinion is based is “generally accepted” as reliable in the relevant scientific community.
The Frye Standard is a foundation of modern expert testimony standards.
The court determines if the scientific method or principle behind an expert’s testimony is generally accepted.
This acceptance demonstrates that the scientific findings are reliable and the methodologies sound
Describe the 1975 Federal Rule of Evidence (FRE)
Established the standard for expert witness testimony.
Requirements:
Expert qualification: A witness must be qualified as an expert through their knowledge, skill, experience, training, or education.
Relevance to the case: The testimony must be relevant and assist the trier of fact in understanding the evidence or determining a fact in issue
Reliable methodology: The expert’s opinion must be based on reliable principles and methods applied reliably to the facts of the case.
Describe Kumho Tire Co. v. Carmichael
The Carmichaels claimed a tire manufactured by Kumho Tire was defective, causing a fatal accident, and their expert witness testimony was challenged by the company regarding its reliability.
Patrick Carmichael was driving a minivan when a a tire blew out, resulting a fatal accident for one passenger and serious injuries to others.
The Carmichaels sued Kumho Tire, claiming the tire was defective and the cause of the accident.
They relied heavily on the testimony of a tire failure expert, Dennis Carlson, who concluded the tire had a manufacturing defect.
Kumho Tire challenged the reliability of Carlson’s methodology, arguing that his analysis did not meet the standards set by Daubert for expert testimony.
The Supreme Court upheld the trial court’s decision to exclude Carlson’s testimony, finding that the judge had the discretion to assess the reliability of the expert’s methods, even if they were not strictly “scientific” in nature.
Supreme Court ruled that trial judges have the authority to assess the reliability of expert testimony in all fields, not just scientific ones, applying the “gatekeeping” role established in Daubert v Merrell Dow Pharmaceuticals to broader expert testimony, including technical fields like tire failure analysis.
It emphasized the need for expert witnesses to have reliable methodologies and sound reasoning behind their conclusions.
What are the four types of examinations conducted by the Image Analysis Program?
- Comparison
1:1 comparison of a questioned individual or object depicted in imagery to known individuals or objects.
This can be faces, clothing, weapons, vehicles, or pretty much anything that is depicted in images or video. - Photogrammetry
The science of taking measurements from images.
Includes height analysis, weapon length determination, vehicle speed analysis, and placement of objects in a scene based on recorded imagery.
Three types:
a. Analytical
Software based – developed by Kodak and National Geospatial-Intelligence Agency (NGA)
Utilizes geometry/references measurements
Used when RPP examinations are not possible
b. Reverse Projection
Involves the projection of an image from a camera onto a new image from the same camera or a camera with similar parameters.
Requires on-site examination – the scene must be unchanged.
c. Direct Scaling
Known distance in a plane that a subject is walking through
i.e.: height chart on a door frame
- Authenticity
Content authentication
Does the image or video depict real people and/or events
Source authentication
Did the camera capture this image
- Information Extraction
Enhancements
Used in most of our other examinations to bring out as much information out as possible out of the imagery.
Examples: Contrast, sharpness, tonality, aspect ratio, etc.
Metadata
Date, time, and location of image taken
iCamera information and settings
What is the difference between manipulation and enhancement?
Manipulation is alternation with the intent to deceive
What are CCDs?
CCD = Charge coupled device
Digital camera that uses a charge-coupled device (CCD) to capture and store images. CCDs are light sensitive sensors that convert light into electrical signals
Invented by George Smith and Willard Boyle in 1969 at Bell Labs
How do CCDs work?
The CCDs surface is broken into pixels.
Each pixel converts light to an electrical charge
The intensity of the charge corresponds to the intensity of the light
The CCD then combines the signal charges to create an image
What are some uses of CCDs?
Security
Access control systems to capture images of people entering a protected area
Microscopy
Optical and fluorescence microscopy to study tissue sections
Astronomy
Storing Astro imaging
What are some advantages of CCDs?
More sensitive than film cameras
Have a greater dynamic range, which means they can capture both bright and faint details in a single exposure.
What does FFMpeg stand for?
Fast Forward Moving Picture Experts Group
What are the FBI Core Values?
Rigorous obedience to the Constitution of the United States
Respect for the dignity of all those we protect
Compassion, extending care and concern whenever possible
Fairness, enforcing the law without fear of favor
Uncompromising personal and institutional integrity
Accountability by accepting responsibility for our actions and decisions and their consequences
Leadership, by example, both personal and professional
Our institutional strength lies in our Diversity
What is the FBI Motto
Fidelity “to the right things.”
Bravery “in the face of adversity.”
Integrity “in all things.”
What is photogrammetry?
The science of taking measurements through imagery
What are the three types of photogrammetry we utilize?
Analytical, Reverse Projection, Direct Scaling
What is analytical photogrammetry?
Software based - software was developed by Kodak and NGA
Utilizes geometry and known/reference measurements
Utilized when RPP examinations are not possible
