Philly had 432 murders in 1995.
Philly was forced to accept to Pa.'s right to law in 1995 and rather late in the year IIRC. Anyway, Philly's murder rate started dropping as you see by the chart in the last link.
Just a coincidence I'm sure.
When the perps are done practicing in Philly, they can come to Detroit for the real ‘thang’.