There is a new and extremely distressing NBER paper by Derek Neal and Armin Rick:
More than two decades ago, Smith and Welch (1989) used the 1940 through 1980 census files to document important relative black progress. However, recent data indicate that this progress did not continue, at least among men. The growth of incarceration rates among black men in recent decades combined with the sharp drop in black employment rates during the Great Recession have left most black men in a position relative to white men that is really no better than the position they occupied only a few years after the Civil Rights Act of 1965. A move toward more punitive treatment of arrested offenders drove prison growth in recent decades, and this trend is evident among arrested offenders in every major crime category. Changes in the severity of corrections policies have had a much larger impact on black communities than white communities because arrest rates have historically been much greater for blacks than whites.