Given his background in journalism, it’s little wonder that director Edward Zwick turned to an investigative reporter’s work as the basis for his latest film, “Trial by Fire.” The film is based on an article of the same name by David Grann published in the New Yorker in 2009 about a Texas man who was almost certainly wrongfully executed for the murder of his three children; DNA evidence exonerated him too late.

Zwick and Grann had both worked together at the New Republic, and he raced to acquire the rights to Grann’s New Yorker article upon its publication in the hopes of turning it into a film. (Geoffrey Fletcher wrote the script, using Grann’s article as the starting point.)

“We acquired the rights nine years ago, and that’s how long it takes to get a movie made,” Zwick said during a sit-down discussion in Washington, D.C. “Particularly movies of this sort. If this were a sequel to a Marvel movie—” he trails off.

In “Trial by Fire,” opening this week, Jack O’Connell (“Better call Saul”) stars as Cameron Todd Willingham, the Texan on death row, with Laura Dern as Elizabeth Gilbert, a Houston playwright and French teacher who wrote to Willingham in prison, came to believe in his innocence, and led a crusade to set him free.

“I think it was a catalog of all the things wrong with the criminal justice system,” Zwick said of Willingham’s story. “I think it was junk science, withholding exculpatory evidence [and] jailhouse snitches in exchange for reduced sentences.

“I think the whole shape was of something that was broken and wrong. And so I felt this was an opportunity to talk about all that.”

Dern had said yes to the project during the lengthy process of bringing “Trial by Fire” to the screen, but in the near-decade of waiting, Zwick watched potential leading men come and go. When he did finally get the green light, he came upon O’Connell, a British actor known largely to American audiences for starring in Angelina Jolie’s “Unbroken” as Louis Zamperini, the GI who spent several grueling years in a Japanese POW camp.

“I needed somebody who was very brave in terms of being willing to portray some of the more less attractive and less reputable parts of the character,” Zwick said of O’Connell, adding that his star worked with famed dialect coach Tim Monich on tackling the Texas vocal affectation.

“His process is amazing. He goes to the [location] and finds the person” with the right vocal inflections to record, Zwick said of Monich, with whom he worked previously on “Blood Diamond” so that Leonardo DiCaprio could effectively imitate a South African timbre.

In a time of hyperpartisanship, tackling the opioid epidemic and criminal justice reform seem to be the only two issues that Democrats and Republicans seem to want to make any headway on. Yet Zwick fears that, at the top of the chain of inequities, is the seemingly arbitrary manner in which the death penalty is applied in American jurisprudence.

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“At the same time, you have a president who called for the death of the Central Park Five before they were even tried and proved innocent,” Zwick said, referring to the 1989 newspaper ads taken out by Donald Trump calling for execution for the five teenagers who were ultimately exonerated of raping a woman in Central Park after years in prison thanks to DNA evidence and a confession by the true assailant.

“I believe when you give the state certain kinds of powers, the state tends to abuse those powers. Whether that’s surveillance, whether it’s drone strikes, if you believe that the state has the power to put somebody to death, I think you’re opening up a Pandora’s Box that could lead in directions that nobody wants to contemplate,” Zwick said. “Revenge is an antiquated, Old Testament concept that has no place” in society he believes.

Whether it was the all-black regiment of Union troops charging Fort Wagner at the climax of “Glory” or the inequities of the trade in precious stones explored in “Blood Diamond,” Zwick’s film are often socially conscious in addition to being entertaining. However, the filmmaker insists that he does not seek out scripts specifically that have an ax to grind or that seek to preach.

But there was one time when he nearly predicted the future, thanks to 1998’s “The Siege,” in which martial law is declared in New York as the government tries to head off attacks by Muslim extremists. This was three years before 9/11, and two decades before President Trump’s Muslim ban.

“It’s not like I’m some prognosticator who tries to anticipate some future shock. But at that time I was looking at what was happening in Europe, and I felt it to be an inevitability here,” Zwick said. “I couldn’t have imagined that this many years later, that it would find another expression. In that case i was anticipating a reality that would elicit an overreaction. And that reality came true.

“In this case”—Trump’s ban—“it’s a false premise that is now engendering an overreaction for political purposes. But it suggests that there’s a strain in the culture of being willing to overreact or support some overreaction.”

Zwick’s films have often dealt with violence in one form or another, though perhaps the most infamous moment of carnage he has ever captured on screen, that of a man’s head blown off by a cannon early in “Glory,” might seem even tame in the era of hyper-violent cable programming.

“Compared to the stuff we just watched on ‘Game of Thrones’ last week, it’s a Disney movie,” Zwick said of “Glory,” adding that after that infamous moment with the cannon, the film’s Civil War battlefield violence is significantly less gruesome, though certainly no less harrowing.

(Turner Classic Movies is re-releasing “Glory” for a limited theatrical run this summer.)

Zwick said he is having meetings with organizations such as the Innocence Project in connection with the issues highlighted in “Trial by Fire.” But despite such extra-textual elements, the director is hopeful that audiences will come to his new film for a quality movie experience.

And if they’re moved to make some change in society as well, all the better.

“I’m now seeing people come out of this almost transcendent,” he said. “There’s a certain kind of catharsis that is uplifting when they see this movie.”

“Trial by fire,” by David Grann (New Yorker)