How has, can, should and will marijuana reform impact the work of defense attorneys?

The question in the title of this post is the central topic of a presentation I am honored to be giving today at the Cuyahoga Criminal Defense Lawyers Association’s annual meeting.  

As is often true when I speak to a group of experienced defense attorneys, I expect I will learn more from the assembled participants than I am likely to teach them.  But, in part because Ohio has not (yet) reformed its marijuana laws in any way, I am cautiously hopeful I can give the group some useful insights about the inevitability of legal and practical uncertainties, especially in the criminal law arena, as to what really happens in a state after it formally repeals blanket marijuana prohibition in some way.

Based on case rulings, policy reports and conversations with lawyers in the field in states like Colorado, I have a general sense of various possible answers to the multi-dimensional query in the title of this post.  But I would be especially eager to hear from any and all persons in reform states if they have distinctive experiences or thoughts in reaction to my question.