The idea that religion is the solution is laughable. If you poll each demographic in America, blacks would probably come out on top as the most religious group while simultaneously being the ones committing heinous, violent crimes at a rate 10x higher than everyone else.
Since you are interested in black crime rates here are a few studies on that topic.
Race and the Religious Contexts of Violence: Linking Religion and White, Black, and Latino Violent Crime.
https://www.ncbi.nlm.nih.gov/m/pubmed/24976649/
Research has demonstrated that concentrated disadvantage and other measures are strongly associated with aggregate-level rates of violence, including across racial and ethnic groups. Less studied is the impact of cultural factors, including religious contextual measures... Results suggest that (1) religious contextual measures have significant crime-reducing associations with violence, (2) these associations are race/ethnic-specific, and (3) religious contextual measures moderate the criminogenic association between disadvantage and violence for Blacks.
Race/Ethnicity, Religious Involvement, and Domestic Violencehttp://journals.sagepub.com/doi/abs/10.1177/1077801207308259The authors explored the relationship between religious involvement and intimate partner violence... They found that: (a) religious involvement is correlated with reduced levels of domestic violence... this protective effect is stronger for African American men and women and for Hispanic men, groups that, for a variety of reasons, experience elevated risk for this type of violence.
Alcoholism Risk Moderation by a Socio-Religious Dimensionhttp://www.jsad.com/doi/abs/10.15288/jsad.2007.68.912Results: Findings indicated that (1) parental alcohol history robustly predicted increased offspring alcohol-dependence symptoms, (2) religious rearing appeared protective (offspring exhibited fewer alcohol-dependence symptoms), (3) religious differentiation accounted for most of the protective effect, (4) other religious variables did not account for the differentiation effect, and (5) black religious adolescents were more frequently raised with differentiating affiliations and exhibited greater protective effects.