When President Obama pledged to close the Guantánamo Bay prison on his first day in office as president in 2009, I believed the country had shifted direction. I was wrong. Four years later, President Obama has not only institutionalized Guantánamo and all the horrors it symbolizes, but he has initiated new extrajudicial programs, like the president’s secret kill list.

In September 2012 I read the news that another prisoner at Guantánamo had died, and I knew I had probably met his family. I traveled to Yemen in 2007 with the idea of making a film about a Guantánamo prisoner. I went there with the Guantánamo lawyer David Remes. He met with families and delivered the news of their sons, brothers, fathers and husbands. I had hoped to film the journey of someone being released from Guantánamo and returning home. Five years later, I find myself making that film, but under tragic circumstances.

Adnan Farhan Abdul Latif recently died in solitary confinement at Guantánamo at age 36, after nearly 11 years of imprisonment there, despite never having been charged with a crime. Last month his body was returned to his family in Yemen, but we are left with many unanswered questions about his imprisonment and death.

Mr. Latif’s death is under investigation by the United States military, which claims he committed suicide from an overdose of prescription medication complicated by acute pneumonia. But that’s hard to take at face value. Why was he placed in solitary confinement when he was suffering from acute pneumonia? How could he have overdosed on medication, given the strict protocols at Guantánamo? Why did it take three months for the body to be returned to Yemen? And finally, why are his autopsy and toxicology report classified and being withheld from his family?