Following the American Civil War, the United States government made a concerted effort to help rebuild the Southern states decimated by the war. This is referred to as the Reconstruction period, which lasted approximately from 1865–1877. During Reconstruction, former slaves and African Americans in general benefited from Reconstruction policies that expanded rights for free men. This, unsurprisingly, angered former slave owners and racist politicians, who enacted a series of prejudiced laws designed to segregate African Americans and strip them of their rights. These new laws—called “Black Codes”—eventually developed into the Jim Crow system of segregation, which spread throughout the South and had long-lasting effects on the black population.

Many of the Jim Crow laws placed restrictions on voting. Such voting restrictions included requirements such as literacy tests and poll taxes. There was also little done to protect African Americans from hate groups like the Ku Klux Klan, who used violence to deter black voters. This kept voter registration amongst African Americans in the South artificially low for many years. More than anything, Jim Crow laws allowed the white ruling class to segregate African Americans, making them lower-class citizens. Segregation meant that black people were prohibited from using the same water fountains as whites, attending white schools, riding at the front of the bus, and much more. This created a social hierarchy in which African Americans were systematically oppressed by the government and the white ruling class.

Michelle Alexander's primary argument in The New Jim Crow is a deceptively simple one: that the legal system has enacted a series of laws that, in their application, if not always in their language, conspire to strip African American of their rights, funnel them into a for-profit penal system, and make it impossible for them to escape the cycle of crime, poverty, and incarceration. These are the “new Jim Crow” laws that are keeping the old social hierarchy in place.

Three strikes laws are laws that mandate harsh sentences for individuals who are repeat offenders. Many states have implemented some version of three strikes sentencing, and the punishment for a third offense is often a mandatory sentence of anywhere between twenty-five years to life. Alexander argues that three strikes laws have dramatically worsened the mass incarceration epidemic by levelling unjust and disproportionate sentences on individuals who commit relatively minor drug offenses.

Over several decades, the Supreme Court has greatly expanded the broad discretionary powers afforded to police officers. Officers may now use supposedly "routine" traffic stops as a pretense to search a person's car for drugs. Furthermore, officers are not required to inform people that these searches are subject to consent, meaning that the person stopped is free to say no. Since most people are too afraid to refuse a request from an officer or are unaware that refusing to give consent is even an option, nearly everyone consents to these requests. Once consent is given, anything a police officer finds during the course of their search becomes legally admissible evidence. Even the smallest amount of drugs can, on an African American, result in an arrest. (White offenders, unsurprisingly, are arrested at an absurdly low rate, if they're stopped at all.)

Following their release from prison, most African American felons struggle to find food, shelter, and work. Federal law prohibits convicted felons from obtaining food stamps, public housing, and welfare benefits. Furthermore, when applying for a job, they're required to check a box identifying them as felons. This makes it hard for them to obtain lawful employment. If they happen to get a job, their wages can be garnished by the government for as long as it takes to pay off the fees associated with their incarceration. This forces felons back into poverty, forcing many of them to return to the illegal drug trade in order to make ends meet. A cycle emerges in which offenders are incarcerated, released, and then incarcerated once more, because the government fails to rehabilitate them and give them the opportunity to become productive members of society.