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Define a firearm. What is the difference between firearms evidence and ballistics? What are the divisions of ballistics evidence? What are a bullet’s class characteristics and what are the individualizing characteristics?

Define a firearm. What is the difference between firearms evidence and ballistics? What are
the divisions of ballistics evidence? What are a bullet’s class characteristics and what are the
individualizing characteristics?
Firearm is any weapon designed to shoot the projectile by explosive action, and it usually the chemical reaction of gunpowder. the legal definition by NJ is “firearms means any handgun, rifle, shotgun, machine gun, assault firearm, automatic or semi-automatic rifle, or any gun, device or instrument in the nature of a weapon from which may be fired or ejected any solid projectile, ball, slug, pellet, missile or bullet, or any gas, vapor or other noxious thing, by means of a cartridge or shell or by the action of an explosive or the igniting of flammable or explosive substances”.
The difference between firearms evidence and ballistics?
The firearms evidence is the examination of evidence that includes tool marks (bullet striation), pattern (burn marks), blood spatter, and fingerprints on the firearm.
The ballistics evidence determines the bullet’s trajectory by measuring the distance the bullet traveled and the Emanating Area where the bullet was located
What are the divisions of ballistics evidence?
The divisions ballistics are divided into internal, transitional, external and terminal.
The internal ballistics covers the processes that happened inside the firearm. (Process of pulling the trigger until the exiting of the bullet of the gun). Then, transitional is when the bullet exits the barrel resulting in striations on the bullet. Next, the external that deal with the trajectory of bullet from leaving the gun and strike the target. Finally, terminal is defined as the impact of the projectile on target.
what are the individualizing characteristics?
The individual characteristics make the bullet unique to a particular firearm that shot a bullet from it. These characteristics may produce randomly from tools used to manufacture the surface of the bullet’s land and grooves’ surface
47.How does glass fracture? How does beveling determine the direction and angle of a bullet
through glass and/or bone?
When an object strikes the glass, it creates ridges, and they are called conchoidal fractures. These conchoidal fractures are parallel to the side, where an object’s force was applied to the glass.
The beveling can determine the bullet’s direction by analyzing the side of the cone-shaped hole formed by the bullet. The small hole on the glass is on the entering side, and the large hole is on the exit side of the bullet. The fractures can also be used to determine the sequence of bullets and their impact on glass, such as the radial fracture. It begins at the bullet hole and flows outward; concentric fractures are formed in a circular pattern around the impact point. These fractures do not interfere with each other, so they stop when they converge with another fracture. The determination of the sequence of bullet holes can be made by analyzing the radial fractures.
How is footwear evidence collected and compared? What are the different methods of lifting footwear impressions? What are the class and individualizing characteristics?
The footwear impressions are one of common evidence that suspects left them behind him at the crime scene, and footwear impressions can be classified into three categories, visible print (patent), invisible ( latent), and plastic (3-dimensional). The footwear evidence collected from the crime scene depends on their classification.
The visible (patent) impressions can be seen by the naked eyes and do not require any aids to developed them; thus, these impressions can be collected by photographing them.
The invisible (latent) impressions are developed in the same way the fingerprints are treated. These impressions need various treatment to collect them from a crime scene, such as powder, chemical enhancement, and different types of forensic light sources. Also, the prints must be photographed in case of any recovery process.
The plastic (3-dimensional) impressions are formed in a soft surface such as mud, snow, and wet sand. These impressions must be photographed before they began collected by casting, lifting, and Bio-foam method.
After collecting the footwear impressions, the examiner is ready to compare the unknown footwear impression with exemplars using transparent overlays or side-by-side examination.
Techniques such as Low magnification are used to detect the defects. Also, calipers are used to measure the defects and their position to other reference points in a shoe. The arrows are used to indicate the similarity and their corresponding feature on comparison impression.
The footwear databases are used to identify the brand style and other shoe features such as SICAR, which help narrow down the field of possible shoes. The examiner’s responsibility is to compare the footwear manually and make a source conclusion.
What are the class and individualizing characteristics?
The class characteristics are the characteristics made intentionally during the manufacture of a collection of shoes. These class characteristics include the brand, style, size, gender, and geometry of pattern on the outsole.
Individual characteristics
individual characteristics that are formed randomly by adding or remove something of the original structure of the shoe. These characteristics include nicks, scratches, cuts, punctures, tears, air bubbles during manufacture, ragged holes. These unique features can be characterized by length, width, relationship to the shoe perimeter, and other defects. these characteristics’ position and orientation of defects are marked, measured, and documented.
Describe the goals and process of blood spatter interpretation.
The goal of the interpretation of blood spatter is to recreate the sequence of physical events that caused the blood spatter. The examiners analyze the blood spatters distribution, characteristics such as shape, size, volume, and relationship to the crime scene to conclude what happened in the crime scene. Blood spatter analysis uses chemistry, biology, and mathematic principles to insist on the examiner to reconstruct the actions and help them include or exclude the potential suspect.
The examiner performed the bloodstain pattern analysis in two phases the pattern analysis and the reconstruction of the crime scene. For the pattern analysis, the examiner analyzes the physical characteristics of the bloodstains such as distribution, size, location of stain, distance, shape, the surface texture. Then the examiner interprets the pattern of bloodstains and what may cause them. The second phase is the reconstruction of the actions that caused the bloodstains. The examiner uses the angle, direction of spatter, and the area of origin to estimate where the victim and the perpetrator positioned when the bloodshed occurred.
How is a blood-spatter documented at the crime scene?
The blood spatters are frequently documented by photographing them from every angle, and a scaler or ruler is placed next to the blood spatter. The scaler is used to provide an accurate measurement. Then, sketches or videos of the crime scene and the blood spatter are taken for analysis and further documentation. The blood spatter collection is not easy to be removed from the crime scene because some evidence may require removing large objects such as carpet or furniture. Blood spatter evidence should be carefully packaged in order to protect them from any damaged. Collecting blood evidence for DNA profile analysis will be performed by using a swab.

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