The social construction of reality refers to a phenomenon that society form a mutually-established both unconscious and conscious consensus about how people should live and behave daily, as well as how to deal with the “ontological status of particulars” (Berger & Luckmann, 1991). The social construction of reality is constantly shared with others horizontally (with the same cohort) and vertically (passing to the next generations) through different types of culture. People take for granted about these shared beliefs and knowledge. In order to articulate the topic of how perceived police legitimacy changes, I specify several key terms based on my understanding from the book: different forms of realities and cultures, the characteristics of traditional and modern media, and its impacts on police legitimacy. I will illustrate how modern advanced media changes the public’s perceptions of police legitimacy, brutality, and implicit racial bias problems by constantly updating and reconstructing our "reality."