Washington and Colorado are in a position unique to drug law so far: having legalized marijuana but still having laws in place pertaining to unlawful intoxication (for instance, Driving Under the Influence), they need to define what the standard for "intoxication" is when it comes to THC. Over time, states have arrived at a general consensus on the intoxication level for alcohol (between 0.08 and 0.12 percent BAC in most states) - a marijuana expert will go a long way toward determining that threshold for THC.
Yes they do. Washington is so out of touch with the issue of marijuana and marijuana enforcement. So many people use the stuff, and it can hardly be considered more dangerous than legal drugs like alcohol and prescriptions. The White House and Congress need to get real on this issue and legalize it.
In fact, I think Washington needs at least two marijuana experts. They need one from a scientific point of view. This person will be able to tell you all about the effects marijuana has on the body, how it is safer than alcohol, and less addictive than cigarettes. They should also have an expert on criminal justice that will show them how the war on drugs ruins lives over a simple bag of pot.
There is already a "drug czar" that has usually been part of the president's cabinet. The issue of pot would fall under their job description. However, such people are appointed by the president without a confirmation process. However, this is a job that does not need to be elevated to a cabinet level.