We think it's a complicated issue, but the biggie is this: Baltimore, or Maryland, or even the United States, could not unilaterally legalize or even "decriminalize" (what's the dif?) alone. Pretty much, all, if not most, of other countries would have to agree and do the same. When people talk about Prohibition, the key element which seems to me is missing is: almost all the other countries of the world remained "wet", while the U.S. tried to go it alone with being dry.
And, unlike booze, the responsibility for policing what are now "illegal substances" would fall on the private sector, even more than they do now. Drunk employees are easily detected at work (usually, if they show up). Drugged employees are not easily detected, except for those whose lifestyle causes absenteeism, lateness, carelessness, and criminal behavior (not just the criminal possession, either).
The fact is that even now, a large percentage of employers, if not a majority, test for illegal drugs for cause, before hiring, or sometimes even randomly. And Buz detects a growing trend in this direction. He and his fellow security consultants typically urge businesses to do so. Since the majority of thefts from businesses occur via your silent partners in the business (your own employees), this is one way of screening your staff, not only against theft, but with regard to getting reliable and safe workers. And in industry, if you get hurt on the job, you will almost universally be asked to take a drug test; test positive: good luck on you workers' comp claim.
So, while I hear a lot of people saying: we should just legalize it, as a public policy, it would be very difficult to implement (of course, in some cities, like Baltimore, marijuana use is all but decriminalized now). Students of public policy, particularly those in medical fields, are going to have a hard time implementing any kind of legalization here in the near future, Prez O's autobiography notwithstanding. It's a complicated issue, and isn't that simple.