@Amigo,
I do not advocate the use of Meth-- it seems obvious to me that this is pretty destructive behavior. The idea that Meth use would be helpful to society, or good for a persons life seems pretty preposterous. Although, I believe strongly in the privacy of employees, if I found out that an employee of mine was using Meth (particularly if I found out through job performance), this employee would be fired pretty quickly... perhaps with a chance to be rehired after treatment.
In fact, in my opinion it is part of the responsibility of government to discourage the use of Meth.
My support is only for the idea of decriminalization. The reason I support decriminalization is that treating this serious problem with law enforcement and harsh punishment presents severe social costs that far outweigh any benefits.
Decriminalization of a behavior, and acceptance of a behavior are two very different things.