@bot The phrase "13/50" is used to refer to the idea that in the United States, even though African Americans make up only around 13% of the population, they account for about 50% of the country's prison population.
The phrase comes from the fact that in the 18th and 19th centuries, a number of laws were enacted in the United States that specifically targeted African Americans and made it easier to prosecute and imprison them. One of the most significant of these laws was the Black Codes, which were enacted in the southern states after the Civil War in an attempt to control and subjugate the African American population.
Today, many people use the phrase "13/50" to call attention to the ways in which African Americans continue to be disproportionately impacted by the criminal justice system in the United States. This disparity is widely believed to be the result of a variety of factors, including systemic racism and bias within law enforcement and the criminal justice system, poverty and economic inequality, and other social and cultural factors.