John Lites was one of the first police officers to respond to a 911 call from Mother Emanuel African Methodist Episcopal Church in Charleston, South Carolina, on June 17, 2015, when a white gunman murdered nine Black people attending a Bible study.

Lites arrived at the scene only minutes after the first emergency call was placed. He held one of the victim's hands as the man died. Lites then stood guard inside the fellowship hall all night — remaining even through a bomb threat — to prevent people who didn't need to be there from entering the room.

"I didn't want anyone else to see it," Lites said. "I was totally traumatized."

Crime scenes are inherently disturbing. A few weeks after the mass shooting in Charleston, Lites found himself in the clutches of post-traumatic stress and unable to sleep. The scene inside the church was imprinted on his memory.

"The worst thing you can possibly think of — it's worse than that," said Lites, who retired from the police force in 2018. "No one else needs to see that."

A question that continues to be debated publicly — and is raised in the wake of each new mass shooting — is whether the publication of violent images, including those depicting gunshot wounds or police brutality, might be effective in preventing future carnage.

Advocates for publishing the images argue that if the public were forced to reckon with the gruesomeness of the deaths, people would respond by demanding that lawmakers enact meaningful reform. The advocates cite historical examples of photos that moved people to action or prompted changes in law or public opinion.

After the brutal death of Emmett Till — a teenager from Chicago who in 1955 was tortured and killed in Mississippi by a group of white men — photos of his mangled body appeared in Jet magazine. Scholars credit those images with galvanizing a generation of civil rights activists.

In 1972, a 9-year-old child named Kim Phuc Phan Thi became known as the "Napalm Girl" after an image of her — distressed, naked, and fleeing a bombed village in Vietnam — was published by The Associated Press. The image won a Pulitzer Prize, turned public opinion against the conflict, and arguably became the most famous photograph depicting the atrocities of the Vietnam War.

"We must face this violence head-on," Phan Thi wrote in a guest essay for The New York Times this year. "The first step is to look at it."

In June, former Homeland Security Secretary Jeh Johnson wrote a similar piece, arguing that such images "do more than speak a thousand words."

"Some actually reveal to us what no words can adequately convey," he wrote.

But there are those, like Lites, who argue that publishing photos of violence runs the risk of retraumatizing survivors, families who lost loved ones, and the public. They say that disseminating graphic photos for mass consumption is disrespectful to the dead and that there is no guarantee pictures from Colorado Springs, Colorado; Uvalde, Texas; Buffalo, New York; Parkland, Florida; Las Vegas, and the hundreds of other sites of mass murders would do anything to prevent future attacks or prompt lawmakers to action.

Moreover, they argue, there is no way to control how the images are used once they are released online. The opponents of publishing fear the photos could amount to "trauma porn," a grisly term used to describe a perverse fascination with tragedy or misfortune.

"The way I see it is America doesn't get to ask me for one more damn thing," said Nelba Márquez-Greene, a family therapist whose 6-year-old daughter, Ana Grace, was killed at Sandy Hook Elementary School in Newtown, Connecticut, on Dec. 14, 2012.

After the mass shooting at an elementary school in Uvalde, Texas, in May, Márquez-Greene wrote a guest essay in The New York Times in which she expressed opposition to the demands placed on families to seek the release of crime scene photos.

Márquez-Greene told KHN that calls to release photos of Ana Grace inside the elementary school began on the same day she was murdered. "It's just so voyeuristic and gross; like, we're literally empowering the masses to make this demand," she said.

Concerns about how images might be used are rooted in history, said Mari Crabtree, an associate professor of African American studies at the College of Charleston.

More than 100 years ago, she said, photos of lynchings across the South were shared to advance very different agendas. The images were sometimes co-opted by racists to "celebrate Black death," she said. But they were also used by civil rights groups — like the nascent NAACP — to raise awareness about the atrocities of the Jim Crow era.

In the early 1900s, the NAACP published and republished violent photos to push federal lawmakers to create anti-lynching legislation, Crabtree said. But it took Congress more than 100 years to pass the Emmett Till Antilynching Act, in March 2022. The amount of time it took to make lynching a federal hate crime casts doubt on the ability of such images to expedite reform, she said.

For her forthcoming book, "My Soul Is a Witness: The Traumatic Afterlife of Lynching," Crabtree decided against including a depiction of lynching on the cover. "Lynching was about dehumanizing Black people into objects of white wrath," she said. "I didn't want it to be reinforcing that."

She also wanted to avoid inflicting trauma on anyone who came across her book — if, for example, it was placed on a coffee table. Consuming images of Black death in such a casual way can be very disturbing, she said.

Images of violence can also cause mental harm, particularly for people who have post-traumatic stress disorder, said Nicole Sciarrino, a psychologist for the Department of Veterans Affairs and an expert in PTSD. Images, videos, and sounds can be "triggering" and exacerbate symptoms, she said. They can also be catalysts that cause someone to ask for help, she added.

Images alone don't cause PTSD, psychologists said. But there is debate about whether watching violence unfold online — such as a live feed of a mass shooting on social media — can inflict a post-traumatic stress response, Sciarrino said.

The Diagnostic and Statistical Manual of Mental Disorders excludes exposure to trauma via electronic media, TV, or video games from the criteria for a PTSD diagnosis. But some psychologists think that should change, Sciarrino said. Their perspective emerged after 9/11, when millions of people watched the World Trade Center towers in New York City collapse on live TV. Photographs taken in Lower Manhattan that day continue to be controversial.

Repeated exposure to graphic images online could desensitize people to violence, said Erika Felix, an associate professor of clinical psychology at the University of California-Santa Barbara. Mass shootings are so frequent that humans often employ a coping mechanism that Felix calls "emotional dampening," a term used to describe the tendency to emotionally tune out.

"Sometimes, scary images do make change," she said. "Sometimes, these things do change public discourse. I don't negate that." But, Felix said, there's also a risk the photos could do more harm than good: "That's a fairly big risk in my opinion."

John Lites retired from police work nearly four years ago, after a hip injury, and then moved with his wife to McClellanville, a rural town on the northern edge of Charleston County.

He takes medication for PTSD but rarely talks about the night of the church shooting.

A few years ago, he attended a training in Columbia, South Carolina, where he met officers from Connecticut, who spoke about their experiences inside Sandy Hook Elementary. Lites recognized himself in their stories. "It helped me move on, which I had not been able to do," he said.

He is disappointed that the 2015 church shooting wasn't the country's final mass casualty event. Lites now views mass shootings in America as a symptom of a much larger mental health crisis.

"We're not doing anything to solve it," he said. "What does publishing those photos do to get us there?"