Evidence is widely available and not difficult to locate:
https://en.wikipedia.org/wiki/Youth_incarceration_in_the_Uni...
>In 1995, African American youths made up 12% of the population, but were arrested at rates double those for Caucasian youths. The trend towards adult adjudication has had implications for the racial make-up of the juvenile prison population as well. Minority youth tried in adult courts are much more likely to be sentenced to serve prison time than white youth offenders arrested for similar crimes.
https://thecrimereport.org/2021/06/17/racial-disparities-per...
>According to the Equal Justice Initiative, Black children are more than twice as likely as white kids to be arrested, even though they’re not committing more crimes, but because Black Kids are burdened by a “presumption of guilt and dangerousness,” which leads youth of color to have higher rates of stops, searches, violence, suspension, and disproportionate contact with the juvenile justice system.
https://www.sentencingproject.org/publications/racial-dispar...
>As of 2013, black juveniles were more than four times as likely to be committed as white juveniles, Americans Indian juveniles were more than three times as likely, and Hispanic juveniles were 61 percent more likely.
http://jaapl.org/content/early/2019/02/13/JAAPL.003828-19
>However, research has documented the existence of racial disparity in the treatment of youth involved in the juvenile justice system for several decades. Studies from the 1980s and 1990s demonstrated that black juveniles were detained and confined at higher rates compared with white youth, and that black youth were more likely to be sent to correctional facilities compared with white youth, who were more likely to be sent to psychiatric hospitals. Additionally, recent studies have documented the continued trend of overrepresentation of minority youth in the juvenile justice system