Sixty-four-year old Roger Christie, a resident of Hawaii’s Big Island, although most recently of Cell 104 at the Honolulu Federal Detention Center, is a Religious Science practitioner, a minister of the Universal Life Church, ordained in the Church of the Universe (in Canada), an official of the Oklevueha Native American Church of Hilo, Hawaii, and the founder of the Hawai’i Cannabis THC Ministry.

As you might guess, it was the last of those spiritual vocations that landed him in prison.

In 2010, Mr. Christie, along with several co-defendants, was indicted on charges including conspiracy to manufacture and distribute marijuana. He does not dispute the facts of the case. He just believes that his operation — “a real ‘street ministry’ serving the needs of our neighbors from all walks of life,” he told me in an e-mail from prison, “busy six days a week,” employing “three secretaries and a doorman” — was protected by the First Amendment.

On July 29, Mr. Christie’s lawyer will argue in Hawaii federal court that his client should be allowed to present a religious-freedom defense at the eventual criminal trial. He will base his argument on the Religious Freedom Restoration Act, passed by Congress in 1993, which requires the government to show a “compelling interest” whenever it “substantially burdens” a religious practice. In 2006, the Supreme Court relied on the act to permit a New Mexico church to use the hallucinogen hoasca, or ayahuasca, for sacramental purposes.

But so far such exceptions have been granted to small religious communities and relatively obscure drugs: for American Indians’ use of peyote, for example, or the New Mexico church with its ayahuasca. But marijuana? That would be problematic.