I won't pretend to agree with all of this (particularly on the way the focus of crime shows has changed in the past 50 years - for what it's worth, I think this is a considerably more complex issue), but it makes for interesting reading.
Since television’s inception, one of its most prevalent genres has been the crime drama (Mawby, 2004). Crime dramas provide interpretative perspectives that shape our thought, in this case about crime (Jewkes, 2004). Crime dramas are morality plays which feature struggles between good and evil, between heroes who stand for moral authority and villains who challenge that authority (Rafter, 2006). The crime genre exhibits stable elements, for example a focus on crime, usually violent crime, and the quest for justice, but it also reflects social change. Over the past 50 years television crime drama has shifted from story-lines in which private detectives or criminal defense lawyers protected their innocent clients, to programs in which police officers apprehend the guilty (Cavender, 2004). Today, the police are the heroes and lawyers are the villains who impede their quest for justice (Rapping, 2003).
Similarly, the crime genre circulates shifting representations of race. Years ago, the genre often was racist: black characters, for example, were colorful ‘extras’ or menacing figures, but, in either case, were portrayed as ‘the other’ and juxtaposed against the usually white protagonist. The situation has changed today, especially on television. When black characters appear, they are more likely to be depicted as members of a legitimate profession like police offi cers than as a criminal (Hunt, 2005). However, the nature of the representation remains problematic. In what Gray (2005) calls an assimilationist style of presentation, black characters typically are in a largely white world where race is not a concern.
The shift toward more dramas about the police organization entails other changes in the crime genre. The narratives in the contemporary dramas not only deal with crime and the efforts to capture the criminal, they also include more details about the police sub-culture and about the personal lives of the police (Wittebols, 2004). These personal lives may be portrayed as home life (McLaughlin, 2005); at other times, the members of the police organization are portrayed as a ‘police family’ (Joyrich, 1996: 48–9). These narratives often have a melodramatic quality, complete with plots that are motivated by the characters’ personal backstories (Mittell, 2004). Stories that utilize these plot devices, for example personal involvement or police family, make the characters seem like ‘real people’, which attracts an audience but also reinforces the cultural meanings that are conveyed through the characters (Wittebols, 2004; also see Jermyn, 2003). Notwithstanding its melodramatic nature, contemporary crime drama is linked with crime news and reality television; indeed, crime fact and crime fi ction blur on television in representing the spectacle of crime (Altheide, 2002; Jewkes, 2004). Crime news, reality programs like America’s Most Wanted, and crime drama all emphasize violent crime (Cavender et al., 1999; Chadee and Ditton, 2005; Roberts and Inderman, 2005). Their presentations are couched in notions of good and evil, and these binary opposites act as emotional, moralistic hooks that draw an audience for news or drama (Jewkes, 2005; McLaughlin, 2005; Roberts and Inderman, 2005). Television’s various depictions of crime weave together realism and melodrama. The result is a forensic style of journalism that dwells on the minutiae of the crime scene (Websdale and Alvarez, 1998) and the forensic realism of television crime dramas like CSI. These factual and fictional depictions of crime are compelling because they offer mutually validating cultural images of crime and the police.
From CSI and Moral Authority: The police and science by Gray Cavender and Sarah K. Deutsch, Crime Media Culture 2007