Do any studies explore increased (or decreased) violent crime or unemployment (or other undisputed social ills) in medicial marijuana states?

Perhaps to the chagrin and annoyance to students in my "Marijuana Law, Policy & Reform" seminar, I keep pushing our class discussion to try to figure out and precisely specify what could be considered undisputed and undisputable harms from any drug legalization regime --- especially if one views simply increased drug use alone, even by young people, to be a social good or at least not clearly a social harm.  (This prior post raised some of these issues and ideas.)  The question in the title of this post is prompted in part by our most recent class discussion, where a rough consensus emerged that increases in violent crime and/or unemployment might be undisputed metrics of a failed social policy.

Thus the question in the title of this post, which also builds a bit off a prior post which asked "Two decades into experimentation, what is really known about medical marijuana practices?".  Specifically, I am wondering if anyone has yet tried (or if it really would even be feasable) to develop effective and sophisticated empirical studies to explore if there have been any statistically significant changes in violent crime rates or unemployement rates in states that have legalized medical marijuana.  

As a relative agnostic (with libertarian leanings) on lots of marijuana reform issues, I believe I would be moved significantly by serious data showing (or even just suggesting) causal links between medical marijuana legalization and violent crime rates or unemployment rates.  Of course, like research on incarceration and crime rates, the results of any such empirical study linking medical marijuana to an increase or decrease in social ills could be disputable and would be disputed by partisan advocates in the reform policy debate.  But for those without a predetermined perspective on various marijuana law, policy and reform issues (which likely describes a majority of Americans), even tentative or partial data showing the positive or negative impact of medicial marijuana and violent crime or other undisputed social harms could and would likely "move the needle" considerably.

This post is intended not only to inquire as to whether anyone is aware of any modern studies exploring these issues in states with medical marijuana laws, but also to ponder whether there are other clear empirical metrics of undisputed social ills that ought to be a central part of the medicial marijuana reform discussion and debate.

Cross-posted at PrawfsBlawg

Recent related posts:

• Are there undisputed benefits from prohibition regimes and/or undisputed harms from legalization/regulation regimes?
• Two decades into experimentation, what is really known about medical marijuana practices?