There are a few things that argue against a bottoms-up approach.
It is a major issue in a number of large cities. And it's the same issue.
Bottoms-up takes too long.
If it was viewed as a problem locally, something would have been done already.
A black man living in city XYZ that has implemented comprehensive reform should not have to worry about crossing into anothe city that hasn't implemented reform. That is a civil rights violation in my view.
And that's exactly what we have today.
So what's the answer? Again, the cities that have the lion's share of the problem are democrat-led cities. Why lay this problem at Trump's feet? I'd be fine with cutting off any and all federal funding to those cities until they get their houses in order. That might light a fire under their collective butts, and that could be done immediately. Do you think the Dems in the House and Senate would agree to it?