Critical criminology is a theoretical perspective in criminology which focuses on challenging traditional understandings and uncovering false beliefs about crime and criminal justice, often but not exclusively by taking a conflict perspective, such as Marxism, feminism, political economy theory or critical theory. Critical criminology frequently takes a perspective of examining the genesis of crime and nature of 'justice' within the social structure of a class and status inequalities. Law and punishment of crime are viewed as connected to a system of social inequality and as the means of producing and perpetuating this inequality. Critical criminology also seeks to delve into the foundations of criminological research to unearth any biases. Critical criminology sees crime as a product of oppression of workers – in particular, those in greatest poverty – and less-advantaged groups within society, such as women and ethnic minorities, are seen to be the most likely to suffer oppressive social relations based upon class division, sexism and racism. More simply, critical criminology may be defined as any criminological topic area that takes into account the contextual factors of crime or critiques topics covered in mainstream criminology. Convict Criminology Convict Criminology which is one type of critical criminology, emerged in the United States during the late 1990s (Ross and Richards, 2003). It offers an alternative epistemology on crime, criminality and punishment. Scholarship is conducted by PhD-trained former prisoners, prison workers and others who share a belief that in order to be a fully rounded discipline, mainstream criminology needs to be informed by input from those with personal experience of life in correctional institutions. Contributions from academics who are aware of the day-to-day realities of incarceration, the hidden politics that infuse prison administration, and the details and the nuances of prison language and culture, have the potential significantly to enrich scholarly understanding of the corrections system. In addition, Convict Criminologists have been active in various aspects of correctional reform advocacy, particularly where prisoner education is concerned. Socially contingent definitions of crime It can also rest upon the fundamental assertion that definitions of what constitute crimes are socially and historically contingent, that is, what constitutes a crime varies in different social situations and different periods of history. For example, homosexuality was illegal in the United Kingdom up to 1967 when it was legalized for men over 21. If the act itself remained the same, how could its 'criminal qualities' change such that it