Americans can look back to the Irish immigrants of the 1850s to see that criminal justice disparities are very often a symptom of vast socioeconomic disparities, not traits inherent to a certain group of people.
News website Pando cited statistics from the history book Immigrant Life in New York City, 1825–1863 to illustrate the big criminal justice disparities low-income Irish immigrants faced in the 1850s:
55% of those arrested NYC in the 1850s were Irish-born
35% of the prostitutes arrested in NYC in 1858 were Irish-born
70% of all admissions to Bellevue Hospital (NYC’s public hospital) in the 1850s were Irish
85% of foreign-born admissions to Bellevue Hospital (NYC’s public hospital) in the 1850s were Irish
63% of foreign-born admissions to the NYC Alms House (Poor House) 1849-1858 were Irish
56% of all prison NYC Prison commitments in 1858 were Irish-born
74% of foreign-born prison NYC Prison commitments in 1858 were Irish-born
70% of persons convicted of disorderly conduct NYC Courts of Special Sessions, 1859, were Irish-born
74% of persons convicted of drunk and disorderly conduct NYC Courts of Special Sessions, 1859, were Irish-born
It wasn't traits inherent to a person's race, ethnicity, or national origin that drove these types of disparities, since Irish immigrants managed to advance socially and economically once they could take on the same opportunities as everyone else. Instead, socioeconomic factors and, yes, racial and ethnic discrimination (there was a lot of anti-Irish prejudice in the 1850s) were at the heart of the problem — and those can often involve solutions beyond the realm of criminal justice policy.
Further reading: "No Irish Need Apply": the fake sign at the heart of a real movement.