Mass murder can be defined as an activity of murdering a large number of people, in a same geographic area which is done in a short period or simultaneously (Abe, 2017). According to FBI, mass murderer is the one who kills four or more people at the same time without a cooling off period. A mass murder usuallt occurs in a single place, where several people are killed by one or more murderers (Abe, 2017). It can also be explained where an organization or a single person, kills a number of people at the same location. Famous examples of mass murder can be seen from the Columbine massacare and the Aurora Batman shooting.A spree murderer or spree killer, is judged on the performance not the quantity of their killings. A spree murderer is termed as the one who kills people over a longer period of time in different locations (Krouse, William and Daniel, 2015). It is also believed that spree murders are done with no cooling off period and is a part of a rapid movement (Krouse, William and Daniel, 2015). Spree murders happen in a rapid time which is not common in the other type of kiilers. Spree killers keep them high on killing, which does not let them stop. It can be from a personal issue or from any conflicts with the establishment (Krouse, William and Daniel, 2015). Famous examples of spree murderers can be taken from Charles Starkweather case in 1958, where a lot of spree killings were done over a long time. According to studies, spree killers might be in groups where one person is the leading partner and other are the submissive partners.A serial killer is the one who commits a series of killings spaned over a long period. Serial killing can be over a course of years or decades, with the same strategy and procedure followed by the killer (Abe, 2017). Serial killers are found to be the favorite nightmares, as shown in horror and action movies as well. The purpose, tactics, and psychology of a serial killer differs from one killer to another (Abe, 2017). Some might be psychological ill and tend to move in serial killing, or some might be born to do this. The famous example of a serial killer can be found from Pablo Escobar, who was a drug lord and a serial killer at the same time. He killed almost 10,000 people including police men and citizens. His era of criminal activities span from almost 5-6 years and was termed as the most dangerous person on earth. So, the difference between a mass murderer, spree murderer, and serial killer is simple that; a mass murder kills four or more people, spree murderer kills two or more people, and serial killer might kill three or more people depending on the location and time (Abe, 2017).Rape trauma syndrome and its involvement in investigating a rape charge.Rape Trauma Syndrome (RTS) can be explained as a psychological trauma, which is experienced by a rape victim after the rape incident. It includes the disorders of an emotional, physical, interpersonal, and cognitive behavior (West, 2016). This theory was introduced by Ann Wolbert Burgess in 1974, which explained these behavior changes in the rape victims. RTS has now been widely researched, and the results gave the identification of the time contstraint associated with rape (West, 2016). It was also concluded that the rape victims usually go through a substance use disorders like, depression, anxiety, complexion disorders, and disruptive eating habits. RTS further develops phases for the rape victims, where some are stable in a short period and some are spanned for a long period of time to overcome the issue (West, 2016).However, RTS plays a significant role in the investigation of the rape charges. It helps the federal authorities to analyze the rape victim that whether, he/she has been a victim of rape or not (West, 2016). Due to the physical and emotional symptoms in the rape victims, it is easier for the authorities to identify the type of charge which will be imposed on the offender.Work CitedAbe, Kenji. “What is a Serial Killer? What is a Mass Murderer? How do they Differ.” European Journal of Academic Essays4.4 (2017): 187-198.Krouse, William J., and Daniel J. Richardson. “Mass murder with firearms: Incidents and victims, 1999-2013.” Congressional Research Service, Library of Congress, 2015.West, Kelsey. “Cultural Effects on Rape Trauma Syndrome: Evaluating the Claims.” (2016).