The organized groups of white men known as slave patrols lay at the roots of the nation's law enforcement excesses, historians say, helping launch centuries of violent and racist behavior toward Black Americans, as well as a tradition of protests and uprisings against police brutality.

As the slave population increased in the U.S., slave patrols were formed in South Carolina and expanded to other Southern states. Slave patrols were not designed to protect public safety in the broadest sense but rather to protect white wealth.

After the abolition of slavery in 1865 with the passing of the 13th Amendment toward the end of the Civil War, slave patrols were done away with and modern police departments become more common.

African Americans, however, were still heavily policed by law enforcement officials. The Ku Klux Klan and other hate groups terrorized Black communities. Some law enforcement and other government officials became KKK members, especially in the South.

During the civil rights era, images of police brutally suppressing peaceful activists, including with the use of dogs and fire hoses, in part helped usher in the Civil Rights Act of 1964, which outlawed discrimination on the basis of race, color, religion and sex. But as Black Americans gained more rights, lawmakers on both sides of the political aisle looked for ways to criminalize the Black community.

From 1980 and 2015, the nation's prison population climbed from roughly 500,000 to more than 2.2 million, with Black Americans making up 34% of all inmates, according to the NAACP. Only 13% of Americans identify as Black, according to the U.S. Census. 

Philimon, Wenei. "Not just George Floyd: Police departments have 400-year history of racism." USA Today June 7th 2020. .