Assignment And Hw
APA 7
ANSWER EACH QUESTION THOROUGHLY
USE REFERENCES PROVIDED AND POWERPOINT PROVIDED ATTACHMENT
You have received Exhibit CS-1, a spent casing, in the lab for analysis. Photographs of this exhibit are located in the PowerPoint, Photographs Exhibits CS-1, attached to this assignment as well as located in Week 4 Content.
This assignment is an application of what you have learned so far in CCJS 441 and in CCJS 301. Also, this is a process assignment. The actual conclusion is not important in this assignment. The important aspect of this assignment is the process. How do you get to the conclusion? Do you understand the process and what happens in the lab? Yes, knowing how to exclude and include is important, but what is the process? That is what this assignment should be focused on.
Please describe in detail the analysis and comparison of this casing. Make sure your description includes the following items:
1. A complete description of the evidence
2. A complete description of the class characteristics visible on the evidence
3. A complete description of any class characteristics you may expect to encounter under the microscope
4. A complete description of the individual characteristics visible on the evidence
5. A complete description of any individual characteristics you may expect to encounter under the microscope
6. How known standards should be obtained.
7. How that class and individual evidence can be used to compare, exclude, and/or include the known standards after the comparison is complete.
Here are some of the readings from this class to get you started:
· The Idaho State Police Manual: Casing Examination is on pages 12-13. Although not detailed, it should get you started.
· The FirearmsID website:
· Cartridge Case Identification
· The Cartridge and Shotshell Examination Module from the Firearms Training
Answers:
- The exhibit is a spent casing (CS-1), which is a brass or metal container that holds the bullet, gunpowder, and primer in a firearm. The casing is typically expelled from the firearm after the shot is fired and can be found at the crime scene.
- Class characteristics of the casing include its shape, size, caliber, and type of primer. The caliber is the diameter of the inside of the casing, which can be measured and used to determine the type of firearm used. The type of primer can also be determined and used to narrow down the type of firearm used.
- Under the microscope, class characteristics such as the caliber and primer type can be further examined and verified. The striations and impressed marks on the casing can also be studied to determine the specific make and model of the firearm used.
- Individual characteristics of the casing include unique marks created by the extractor, ejector, and breech face of the firearm. These marks are unique to each firearm and can be used to positively identify the specific firearm used in a crime.
- Under the microscope, individual characteristics such as the extractor and ejector marks can be examined and compared to known standards obtained from test firings of the same or similar firearms.
- Known standards for comparison can be obtained by firing the same or similar firearms into a recovery media, such as water or sand, and then collecting the spent casings for analysis.
- The comparison of the class and individual characteristics between the evidence casing and known standards can be used to determine if the casing came from the same or similar firearm as the known standards. This can be used to exclude or include a suspect firearm and to support or refute the involvement of a specific firearm in a crime.
