Broadly speaking, the term racial threat refers to how people react to those of a different race. More specifically, the racial threat hypothesis or racial threat theory proposes that a higher population of members of a subordinate race results in the dominant race imposing higher levels of social control on the subordinate race, which, according to this hypothesis, occurs as a result of the dominant race fearing the subordinate race's political, economic, or criminal threat. Research has shown a strong association between the size of a state's nonwhite prison population and the likelihood of that state enacting a felon disenfranchisement law, which supports a link between racial threat and the passage of such laws.
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Racial threat Wikipedia(Text) CC BY-SA