What I wonder is how many people were originally detained/investigated because of the WoD, but arrested/prosecuted for the non-drug offenses. (i.e. resisting, gambling, tax evasion, etc.)

Unless you know why these people were in front of the cops to begin with, you can't speak to whether any given policy change will or won't affect arrest or imprisonment rates.

e.g. Stop-and-Frisk is a War on Terror policy, but regularly results in weapons and drug charges. Are the people ultimately sentenced for those offenses in prison because of weapon or drug laws, or anti-terror laws?