Christopher J. Harris, a professor at the University of Massachusetts-Lowell, used data from various studies to test his theory that there may be certain types of officers that are more susceptible to using force and also that certain situational factors (like circumstances/environment and the suspect/victim involved) increase the chances of force being used. His hypothesis was right in that there are certain situations and types of officers more prone to have an improper force incident. Out of all the data roughly 4-5% of cases showed use of force; of that 2.3-3.3% were shown to have been reasonable force, while only 1.3-1.8% were improper use cases. Young, inexperienced, male officers tended to be more likely to use improper force while aggressive/hostile,