DEVOTED SISTERS: Institute Professor Patricia Crone and her filmmaker sister Diana C. Frank on a New York Street. Originally from Denmark, the two have collaborated on the documentary “For the Life of Me: Between Science and the Law,” which chronicles Ms. Crone’s search for marijuana after she was diagnosed with lung cancer. The film was shown at the Institute for Advanced Study Sunday. It is hoped that it will air on PBS at some time in the near future. For more information, visit: www.forthelifeofmefilm.com.

Until recently, Patricia Crone was a familiar sight around Princeton, riding her bicycle (without a helmet) to and from the Institute for Advanced Study where she is professor emerita of Islamic history. At times, as I passed her in my car, I had to stifle the urge to call out to her about that. I worried about that lovely blond-bobbed head and the brilliant brain within.

A new documentary film For the Life of Me: Between Science and the Law opens with Ms. Crone’s head full-frame. Her strong slightly-accented voice launches into her subject: marijuana and her search to get hold of enough of it to test its purported medicinal benefits. “I have cancer. It will grow and will eventually kill me,” she announces boldly.

In November 2011, when Ms. Crone was diagnosed with lung cancer, it had already spread to her brain. Her options were few and grim. But her response was all business. She made her will, thought about what was needed to finish her latest book and had surgery to remove a third of a lung. She also did what she is good at: research.

The film, which screened in rough-cut at the Institute for Advanced Study on Sunday, shows every step in the process of Ms. Crone’s decision to use marijuana in her fight against lung cancer. Produced and directed by her sister, Diana C. Frank, the work is deeply personal. It is also a highly professional exploration of its subject. Ms. Frank has worked for ABC, NBC and PBS. She has a PhD in linguistics from Cornell and has written for The New Yorker.

Ms. Crone attended Sunday’s screening and the reception that followed in a wheelchair. She smiled a great deal, clearly pleased to be there and proud of her sister’s filmmaking accomplishments.

The documentary shows Ms. Crone Googleing “Rick Simpson’s Oil,” touted for its tumor-shrinking properties, about which the accomplished academic acknowledges skepticism, but what does she have to lose? Having discovered that the National Cancer Institute describes some of the chemicals in marijuana, or cannabis, as having cancer-fighting potential, she decides to try it.

Then, in August 2012, she is advised to have whole brain radiation and faces a stark choice. Should she undergo whole brain radiation and risk damage to her brain and to her ability to conduct the research that is her joy? Or should she give marijuana in the form of “Rick’s Oil” a chance? She decides to postpone the radiation treatment.

Her search for a pound of cannabis takes her to upstate New York and ultimately to Oregon. When she gets her hands on some, she brews her own batch of Rick’s Oil in her Princeton backyard. The fumes are unpleasant to her and when she takes too much bread dipped in the dark thick liquid she finds the results decidedly “unpleasurable.”

Ms. Crone knows that if she was caught with a pound of pot, she could be treated as a dealer and perhaps even deported to her native Denmark.

In effect, the film is Ms. Crone’s confession to breaking federal law. Although New Jersey, like 22 other states, has legalized marijuana for medical use, it is classified as a Schedule I drug by the federal government. According to the Drug Enforcement Administration, Schedule I drugs are defined as having “no currently accepted medical use and a high potential for abuse. Schedule I drugs are the most dangerous drugs of all the Drug Schedules with potentially severe psychological or physical dependence.” Cannabis is classified alongside heroin, lysergic acid diethylamide (LSD), 3,4-methylenedioxymethamphetamine (ecstasy), methaqualone, and peyote.

Meanwhile, the National Cancer Institute describes marijuana as having anti-metastatic and tumor-shrinking qualities, but federal laws impede the development of the drug’s medicinal potential. And while it’s legal to buy in New Jersey for medicinal purposes, it’s not easy to get hold of it, as Ms. Crone’s story demonstrates, simply because it is illegal to grow without going through an extremely costly application process.

Ms. Frank’s film traces changing attitudes to “pot” from the 19th century, chronicling the introduction of the 1937 tax on cannabis that was fiercely opposed by the medical community, which then considered the drug a valuable medicine. It describes a process fueled by ignorance and hysteria, and the scaremongering tactics of the Federal Bureau of Narcotics led by Harry Anslinger. By 1942, cannabis had been removed from the American pharmacopeia. In 1971, Nixon called it “public enemy No. 1.”

What Ms. Crone learns from her “adventures in potland,” she is eager to share with her doctors and is amazed to find they know little to nothing about the medicinal properties of cannabis. “Why?” she asks. And promptly goes looking for the answer.

We see Ms. Crone with a series of research scientists: Sunil Aggarwal, who looks for cannabinoid receptors in the brain; Ohio University’s cancer researcher Ramesh Ganju and neuroscientist Gary L. Wenk who discusses some surprising results concerning cannabinoids and the aging rat brain; and Allan Israel Frankel in Los Angeles who recommends “a puff a day,” and would like to see cannabis “as legal as cucumber.”

In an effort to understand the situation she finds herself in, Ms. Crone meets with epidemiologist Ernest Drucker of the Albert Einstein College of Medicine and author of A Plague of Prisons: The Epidemiology of Mass Incarceration in America, published by The New Press in September 2011. She consults leading marijuana reform activist Jon B. Gettman, whose 1995 petition to remove cannabis from Schedule I of the Controlled Substances Act was denied; his second petition filed in 2002 is still under review by the Department of Health and Human Services. She is also shown with her Princeton oncologist David Sohar.

Ms. Crone speaks in a confident and wry tone that is heartbreaking given that the ending to this story is never in doubt; only the time-frame is under dispute.

The documentary is not without humor. In fact there is a great deal of humor as when Ms. Crone comments on the history of the drug that was once a commonplace for doctors in the past and is now classified as having no redeeming medicinal properties. “I’ve no cannabis, but lots of deadly prescription drugs,” she says. She also notes: “If any of my Institute colleagues get high it’s more likely to be on ideas than on pot.”

In the end, when she begins to see symptoms of deterioration, Ms. Crone opts to have whole brain radiation. But she believes that the marijuana treatment has helped her. While using it, she was able to put off having the radiation treatment not once but twice, thereby avoiding probable damaging side effects to her brain for a period of 7 months.

The last shot is of Ms. Crone having her hair cut in April of this year. Her hope is that her experience and the film will promote future research into the endo-canabinoid system.

The film raises numerous questions. Why do big pharmaceutical companies seem uninterested in researching cannabis?

Change will no doubt come. But, as Ms. Crone observes, too late for her. What a loss of another beautiful mind.

Introducing her film, Ms. Frank pointed out that it would soon be finished. She hopes it will be shown on PBS in the near future. A kick-starter campaign is raising the necessary funds to do so. Let’s hope it will be shown at the Garden Theater one day.

For more information, including a film trailer, visit: www.forthelifeofmefilm.com.

The website includes numerous links to documents on cannabis and cancer such as the National Cancer Institute (www.cancer.gov/cancertopics/), it also points out that while there is much preliminary evidence that cannabis is effective against several different cancers, until the drug becomes FDA approved medicine, it is not advisable to forgo conventional treatments.