Coincidence? She thinks not...
And I agree with her.

[I]t is no coincidence that the War On Drugs heated up after the civil rights movement achieved a set of huge victories that gave this country a moment of hope for something like racial equality. Now we have a country where 1 in 15 black people are currently in jail.

Amanda Marcotte, "The brainless, pointless War On Drugs", March 6, 2008

One should also remember that a real wave of felony disenfranchisement laws gained steam at around this time. As the law in the USA currently stands::
* only two US states have no laws on voting by felons;
* only inmates convicted of a felony are barred from voting (with their right to vote restored upon release from prison) in 13 states;
* felons (in prison and on parole) are barred from voting but can vote upon completion of parole in 5 states;
* inmates, parolees, and probationers are barred (and so can vote only upon completion of all supervised release) in 20 states;
* inmates, parolees, probationers, and ex-felons are completely barred from voting (restoration of voting varies by state) in 10 states.

Given that Blacks are grossly disproportionately represented in the American prison population it should come as no surprise that every single state of the former Confederacy is found in the two categories with the toughest restrictions, as are three states which were Confederate Territories in whole or in part, as are three states that remained in the Union but had majority-Reb populations, and "bleeding Kansas", which is currently aggressively pro-GOP. (Further, many of the felony disenfranchisement laws in the Old South started during Reconstruction as the former Confederate states cast about for ways to prevent their'n newly free and unacceptably uppity niggers from votin'.)

Don't forget that these lists don't have to be accurate to stop a person from voting. By way of example: many, many people in Florida (mostly Black) in the notorious 2000 presidential election found themselves unable to vote because of being erroneously listed as having felony convictions, and could not get their right to vote restored in time or at all. (It was, I'm sure that we all agree, just a coincidence that the list was provided by a Texas GOP firm to a state with a GOP governor, a GOP legislature and a GOP Secretary of State - Katherine Harris - who was disgustingly overt about her efforts to stop people from voting Democrat. And most Blacks vote Democrat. Just a coincidence.)