This piece was reported through The Marshall Project, a nonprofit news organization that covers the U.S. criminal-justice system.

The pictures, for the most part, are prosaic, like outtakes from a yearbook photo shoot. One shows five members of an amateur rock band. Another depicts uniformed football players gathered for a team photo. In yet another, a man is shown carving an ice sculpture. Occasionally, though, the subject matter is much darker.

One photo comes with caption information: “Martinez Killed in Yard, 1963.” It shows empty bleachers and what appears to be blood spatter in the foreground. The yard is in San Quentin Prison. And once you know that, there is nothing prosaic about any of the photos.

There are at least 10,000 negatives, most of them unprocessed, that date from the late 1940s to the late 1980s, stuffed into cardboard boxes and unexamined for decades. The negatives came to the attention of San Quentin’s public information officer, Lieutenant Sam Robinson, about four years ago. He showed them to Nigel Poor, a professor at California State University, Sacramento, who had been teaching a history of photography course at the prison.

“My heart just exploded,” Poor said. “As an artist, or a photographer, or a collector, you couldn’t wish for a better box of treasures.”

The pictures were taken by prison-appointed photographers, usually corrections officers, whose job was to document life at San Quentin. But what prison officials had intended to do with the photos seems unclear. Poor was permitted to take home an envelope containing about 100 negatives. After scanning a few dozen and showing Robinson some prints the following week, Poor got the entire box to work with. And then more boxes. She’s been processing, scanning, and categorizing the work ever since.

Inmate banquet, 1978 (San Quentin State Prison)

For Poor, the overriding lesson of the archive is that life inside San Quentin, for the most part, is occupied by activities and concerns common to us all. Violence is not the mainstay.

“What’s interesting to me is how much normalcy you see in the pictures — work, education, health issues; the same things we outside go through,” she said. “I think the photos humanize the people inside prison.”

Poor uses the photos as teaching tools to draw out the emotional content of the photos. Once she has printed selected photos on large card-stock with wide white borders, she encourages students to write out their thoughts and impressions in the margins, or on the images themselves. Prisoners are writing current stories about an institution that dates to the 1850’s. They’re examining their connections to the the lives of inmates who came before them. Poor calls this archive mapping. “It gives them a lot of power,” she says. “Archive mapping allows them to talk about their own experiences’’ and reflect on their upbringing, the nature of punishment, personal relationships, accountability, social codes and much more.

Archived mapped image (San Quentin State Prison)

Beyond the catharsis and the potential therapeutic gains for the men, Poor hopes the mapped photos may spark the interest and empathy of the public. In fact, she thinks her students’ voices are the only way to humanize an otherwise stereotyped population.

“The incarcerated men's responses have to be the core,” she says.

Researching and preserving such a vast trove will take years. At present, prison officials are entrusting Poor with the task. Eventually she envisions an online archive, with the images cross-referenced across themes, and perhaps a book.

For now, week-to-week, Poor and her students continue to analyze what they have found.“I can use this picture to talk about race in prison, or that picture to talk about homosexuality in prison. And this one, maybe, about what it’s like to spend holidays locked up and away from family.”

“These images,” she says, “represent difficult conversations.”

Dummy found in cell, 1963 (San Quentin State Prison)
Parker escape attempt, 1966 (San Quentin State Prison)
Two inmates and seal, 1974 (San Quentin State Prison)
Divans, 1971 (San Quentin State Prison)
Football, 1974 (San Quentin State Prison)
Self-inflicted wound, October 7 1963 (San Quentin State Prison)
Death by stabbing in South Block, 1965 (San Quentin State Prison)
Mrs. Gorham, no date (San Quentin State Prison)

Killed in Lower Yard, 1965 (San Quentin State Prison)
Found hole, 1963 (San Quentin State Prison)
Inmate Banquet, 1978 (San Quentin State Prison)
Wedding, no date (San Quentin State Prison)
Weapon and contraband, February 9, 1964 (San Quentin State Prison)
UT taking pulse, no date (San Quentin State Prison)
Profile, August 24, 1974 (San Quentin State Prison)
Public relations activity, 1974 (San Quentin State Prison)
Venerable suicide hospital room, 1965 (San Quentin State Prison)
Martinez killed in yard, December 14, 1965 (San Quentin State Prison)
Soul Day, August 9, 1975 (San Quentin State Prison)
Big Gaunt gym profile, July 15, 1975 (San Quentin State Prison)
Ice sculpture, July 22, 1975 (San Quentin State Prison)
Fish caught at dance, September 17, 1975 (San Quentin State Prison)