The fictional case is a perfect example of a criminalistic act where crime is solved using criminalistic science. It is a science that uses various procedures, formulas, and methods in the collection, analysis and in evaluation of evidence which can be used in a legal proceeding to unearth, prevent, expose or investigate a crime.
The most important thing while approaching a scene of crime is to avoid the interference, disturbance and contamination of possible evidence. In the case in hand, the samples which I would collect from the crime scene are; 1) the body of the victim, 2) Trace evidence such as the strip of grass at the scene of crime, twigs and leaves from the hair, grass fragment in her pubic hair, body hair, the soil dirt at her left thigh, 3) Garments such as the white T–shirt, the purse, the pair of blue denim jeans, a wrist watch, 4) Sample of blood in her left arm and breast, saliva and mucus. 5) I would also take photographic evidence. 6) Impression evidence such as the drag mark in between the body and the path. 7) Medical evidence of the autopsy carried out by the pathologist. 8) Toxicological analysis of blood alcohol and urinary alcohol.
The investigation of these samples woud assist in the investigation in that the dead body itself would be sure evidence that the murder occurred. The trace evidence collected would help in the analysis of the relationship between the suspect and victim. For example, the twigs and leaves would be examined for fingerprints of the suspect. The blood samples, saliva and mucus would be used in serology to determine their true origin and identity. This is the blood in her left arm and breast. The photographic evidence would be used to preserve the identified crime scene and evidence that might be erased. Toxicological analysis would form the basis of drug identification process to identify harmful substances administered to the victim such as alcohol. The blood stains would also be subjected to DNA typing which would provide the genes of the suspect since people have unique DNA.
The advantage of attending the crime scene is that it provides first hand evidence about the case. Investigators would be in a position to question possible witnesses. The advantage of attending the crime scene and collecting DNA evidence is that the DNA test will be used to solve the murder case. The DNA cells are found in almost all body parts, be it in the hair, nails, blood, saliva or mucus and it can be used to conclusively determine the innocence or guilt of a suspect. The other advantage is that the investigators would be able to figure out the position in which the victim was and how the victim was positioned and thus they would make a conclusive report.
The disadvantage is that the job is extremely risky since the investigator may be attacked and killed by the suspect in the process of collecting evidence. Another disadvantage is that there may be lack of expertise, experience, awareness and tools necessary to gather the required evidence. The investigators attending the scene may not have the full knowledge and role of the evidence, its limitation and its strength. The investigators may not have the best tools and methods necessary to collect evidence. The other disadvantage of attending the scene of crime is that the criminalists are exposed to diseases. This is whereby the victim may be suffering from a disease and it then spreads to the investigators. A good example of this disease is HIV/AIDS. If the patient was suffering from this disease, the investigator may contract it while collecting blood samples if he pricks himself with a needle. The other disadvantage is that some of these methods are susceptible to human errors and can lead to drawing wrong conclusions.