In 1961, a rubber tapper at the heart of the Amazon forest founded a religion known as the Uniao do Vegetal (UDV). Essential to the practice of this religion is the ritual, sacramental, use of a psychoactive tea called Hoasca (also known as Ayahuasca). Today, the UDV has followers throughout Brazil as well as in the US, Spain, Portugal, England, Switzerland and Australia. In 2005 the United States Supreme Court, in a historic unanimous decision, affirmed the right of the UDV to use its sacrament. This decision was recognized as having "changed the landscape of the law" relating to religious...