CJ 328 Unit 9 Assignment 2

CJ 328-01: Forensic Fingerprint Analysis

Unit 9 Assignment 2

Purdue University Global


In this assignment, I am called out to a local gas station for a murder scene, and this is because I am an CSI. Upon arriving at the scene, I am informed that there was another employee inside the store along with a woman and her son who is a teenager. They all saw what had occurred. The first responding officer has already secured the scene and taken all of the photographs and interviewed the people. I was made aware of eight items the first thing is a paper lottery ticket that is located on the counter, it contains a stain of what resembles a bloody impression of a possible fingerprint, the next thing that I am made aware of is a .38 caliber revolver and there are some spots which may be blood and something that appears to be hair and fibers on it, there is a carton that is made out of cardboard that is in the floor near the counter, there is also a map that has the directions to the store, there is a cardboard six-pack hold that contains beer bottles that is located near the beer cooler, there is also a bullet that was fired into the wall located behind the counter, there is a cardboard box that contained some money that has been spilled on the floor and located near the body of the deceased victim, and there is also a cigarette butt that appears to have been smoked that is located in the parking lot close to the front of the store.

There will be fixed, along with items that are non-movable that will be checked for any latent fingerprints, plus there will be some items that will not be checked for latent impressions. There will be some items checked at the scene for prints and then there will be some sent to the lab, and the methods will be discussed.

The paper ticked will be processed and all carboard materials would be checked for latent prints at the scene and this would be done by black powder and lifting tape. Once the prints are lifted, they will be placed into a paper envelope and tagged with the needed information.

The needed information would include the date and time, the case number, and the initials of the person bagging the prints (Fisher, & Fisher, 2012). Once this is done then the evidence will be sent to the lab for more testing. The cigarette butt that was located will be checked for DNA, and this could eliminate the suspect and the victim as being the person that smoked it.

The unmovable items that would be processed would be things such as doorknobs, handles that are located on the cooler doors, all countertops, the cash register, and black powder and lifting tape would be used to do this. Again, the prints would be placed into the proper containers and sent to the lab. The stain that may be blood that is on the paper ticket would be swabbed and then allowed to airdry and then packaged and labeled and sent to the lab (Federal Bureau of Investigation, 2006).

The best way to retrieve the what appears to be hair and fibers from the weapon would be done by using a pair of tweezers and it would be placed into a paper envelope and labeled with the proper information. The weapon should be picked up by the barrel and placed into a separate paper bag and the ammunition and the magazine clip would be packaged separate (Fisher, & Fisher, 2012).

As for the non-porous items such as the doorknobs, cooler door handles, cash register, and countertops would be processed. It is so important that all of the evidence is properly handled and packaged because if not it can lead to cross contamination and if this were to occur then it could destroy the entire case. This could result in an innocent person going to prison or a guilty person being set free (Triplett, 2004). The bullet that is lodged in the wall located behind the counter will be cut out and sent to the lab, because if I were to try and dig it out then there is a chance that the evidence could become damaged. All of the collected evidence mentioned above will be sent to the lab for more testing.

In order to find out if any of the people that was at the crime scene were involved or if they were only a witness to the crime, the following would be done.

Their behaviors would be closely observed. They would be asked to reveal their names and they would be given a gunshot residue test, and they would be fingerprinted, and this would be done to eliminate them from being a suspect of this crime (Lee, & Gaensslen, 2012). I personally would not be doing this because I am not the detective that is assigned to the case.

The investigator would go more in depth with interviewing them and this may take place at the scene or perhaps the police station (Fisher, & Fisher, 2012). Chances are the mother and son would be interviewed separately and then their answers would be compared, and the employee that was present would also be interviewed and all answers would be compared to see if they were in fact the same story.

The steps to packaging evidence that is in relation to fingerprint analysis:

There are several different types of evidence such as, physical, bullet holes, blood, weapons, hair, fibers, and the list goes on and on. The most important thing is to collect all fingerprints at the crime scene, and it should all be placed into a paper container such as an envelope, and it should be tagged and labeled with the needed information (Layton, 2005).

When a person has been charged with this crime, there will be an expert witness that will testify at the hearing. What qualifications and training does one have to have in order to be an expert witness?

Whenever a person testifies at a hearing as an expert, he or she has to be competent on the topic. They have to have training and be up to date on the knowledge of the topic. They must test the evidence that is related to the case and in this case, it would be the fingerprints that were recovered at the crime scene (Lee, & Gaensslen, 2012).

The witness’s testimony has to be built on facts and information about the topic. The witness has reliably applied the principles and methods to the facts that are related to the case. For example, a fingerprint examiner expert witness would have to be trained in the forensic fingerprint education, and he or she would be qualified through their knowledge, skill, training, practical experience of this topic (Lee, & Gaensslen, 2012). Not just anyone could testify about fingerprinting unless they have the knowledge and training and education that comes along with being a fingerprint expert examiner. By the expert being trained and qualified to testify this could make the case and put the suspect in prison. The witness also has to be both reliable and credible.


Federal Bureau of Investigation. (2006). The science of fingerprints, classification and uses.

Retrieved from: http://www.dermatoglyphics.com/sof/

This is a credible source because it is a suggested reading for fingerprinting classes.

Fisher, B.A.J., & Fisher, D. R. (2012). Techniques of crime scene investigation. (8th ed).

Boca Raton, FL: Taylor & Francis Group.

This is a credible source because it is a textbook used to teach criminal justice classes.

Layton, J. (2005). How crime scene investigation works. Retrieved from:


This is a credible source because it is a website that contains information on how to work a crime scene.

Lee, H. C., & Gaensslen, R. E. (2012). Advances in fingerprint technology. (3rd ed).

Boca Raton, FL: CRC Press.

This is a credible source because it is a textbook used to teach criminal justice classes.

Triplet, M. (2004). Fingerprint dictionary: A collection of over 100 terms used in the science

of fingerprint identification. Retrieved from: http://www.nwlean.net/fprints/html

This is a credible source because it is a website that contains information about fingerprinting.