In United States, the correlation between ethnicity and class has been weal is a TRUE statement.
Explanation:
The ethnicity data is absent for some areas and the racial or ethnic disparities may be understated in US. The black and white and Hispanic and white ratios is lesser because the Hispanics are included in the white person and the white rate of incarceration appears higher.
Alabama, Maryland, Vermont and Montana are the 4 states that did not reported data related to ethnicity to the state department of corrections' individual reports or to the Justice Statistics Bureau. This is the reason for the weak correlation between ethnicity and class in US.