One of the easiest things in criminal drug law is to add new drugs to the drug schedules. 

For the uninitiated, the federal government and the states sort medications and drugs into schedules. 

Schedule I are drugs that the government claims have no currently accepted medical use and a high potential for abuse.  Currently, that list includes LSD, ecstasy, methaqualone, and peyote.  Oh, by the way, in spite of a number of states having medical marijuana laws, the schedule includes marijuana, also referred to as cannabis.  It also includes psilocybin, found in so-called magic mushrooms.

Schedule II are drugs with a high potential for abuse or dependence but which have a medical use.

Schedule III are useful drugs which have a low or moderate risk of abuse or dependence.

Schedule IV includes useful drugs with a low potential for abuse or dependence.

Schedule V are drugs with an even lower potential for abuse or dependence.

If you are interested in learning more, take a look at the article on the DEA website.

According to news coverage, Johns Hopkins researchers are currently in Phase III clinical trials on psilocybin.  That research may lead them to request the re-categorization of the drug from Schedule I to Schedule IV.  This means that the research shows that mushrooms are not particularly subject to abuse or dependence.  

The research, at this point, is focusing on the use of the drug for treatment of smoking cessation, cancer-specific depression, and anxiety.  

Animal testing has shown it not to cause the kind of compulsive use present with cocaine, alcohol or heroin.  It also shows the drug to be pretty safe with the lowest potential for lethal overdose of similarly classified drugs.

Something to watch for.  But, even if the move happens, you will still need a prescription for legal use of the drug.