Indeed, cannabis is one of the few substances on earth that can't kill you. It was classified as a Schedule 1 drug under the 1970 Controlled Substances Act, suggesting the potential for abuse, a concern about safety and the absence of an accepted medical use. But subsequent research has shown that cannabis is not physically addictive, as many illicit drugs are, and that it could make life better for people with a range of ailments, such as Tourette's, irritable bowel syndrome, anxiety, glaucoma, spasticity, Huntington's disease, chronic pain and intractable epilepsy. And the safety concerns have turned out to be unfounded. "Nearly all medicines have toxic, potentially lethal effects," a Drug Enforcement Administration administrative judge wrote in 1988. "But marijuana is not such a substance. There is no record in the extensive medical literature describing a proven, documented cannabis-induced fatality." So even parents who might not have my penchant for methodical experimentation would have little to fear in using it to treat children like mine.