Well, I have a few things to say about this. The 'ethical' issue is that government isn't sure where the 'doctors' really are positioned on the issue.
The 'doctors' could manipulate the medical marijuana sector, like they have already with the legal drug manufacturing sector. Many doctors prescribe medicine for almost any ailment. This drives up legal drug manufacturing profits.
Herbal remedies are again being pushed out or degraded, as not effective versus drugs from drug manufacturers. This is clearly was is happening, but is happening because the drug manufacturers have lied.
The federal government doesn't know how many medical marijuana patients are really sick? Here lies the problem.
Medical Marijuana is for many different cases. Some people are put on it, by a case by case basis. The fact that other individuals have tainted the medical marijuana market with 'real' herb, then it would ethically make realistic to pass legislation and legalize it. How ever, on the other side of the coin-
Other drugs, like cocaine and heroin, meth and crack, should carry higher or stricter punishment. These are more potent and a lot more dangerous, and can bring on hallucinations.