In 1940, when Sid Grossman took a series of photos documenting American labor unions, he probably didn’t expect his activities to attract the attention of the government. Yet seven years later, those same images served as the justification for the US attorney general, Tom C. Clark, to classify Grossman’s New York Photo League as “subversive”  — a particularly dangerous label at the start of the Cold War.

The League tried to exonerate itself by assembling a 1948 exhibition titled “This Is The Photo League.” But in 1949, League member Angela Calomiris, an undercover government informant, inflicted a fatal blow by falsely testifying that the League was a front for the Communist Party. Membership plummeted, and the League shut down in 1951.

Founded15 years earlier by Sol Libsohn and Grossman, the New York Photo League had been a cooperative of professional and amateur photographers who shared the goal of promoting social justice through their images. The League’s mission statement declared, “Upon the photographer rests the responsibility and duty of recording a true image of the world as it is today.”

The group hoped its images would lead to change, adding, “[the photographer] must not only show us how we live, but indicate the logical development of our lives.”

Until Jan. 21, the results of those efforts are on display as part of “The Radical Camera: New York’s Photo League,” presented by San Francisco’s Contemporary Jewish Museum.

Like many Photo League images, Consuelo Kanaga's 1937 "Untitled (Tenements, New York)" captures the poverty and daily struggles of the Great Depression. (Courtesy of the Contemporary Jewish Museum)

Like many Photo League images, Consuelo Kanaga’s 1937 “Untitled (Tenements, New York)” captures the poverty and daily struggles of the Great Depression. (Courtesy of the Contemporary Jewish Museum)

“The exhibit is an opportunity to showcase and celebrate the role of first-generation Jewish-Americans in the history of photography, shaping how the documentary photograph took shape as a social activist form,” says Colleen Stockmann, the museum’s assistant curator. “This question of social activism through photography has a strong argument: that it’s an extension of a broader Jewish social activist culture and history.”

The majority of the League’s members were indeed Jewish, and represented a popular, left-leaning segment of American Jewish thinking at the time.

“Everyone was to the far left back then, smack in the middle of the Great Depression,” says Mason Klein, curator of fine arts at the Jewish Museum in New York, which displayed the exhibit last year. “There was a need to reveal the conditions under which people lived, particularly in the urban environment of New York.”

Through the photographs, visitors can clearly see the anguish and squalor that were the norm for much of the population during the Depression and beyond.

Lisette Model’s simply titled “Lower East Side 1940,” for example, introduces viewers to an unnamed middle-aged gentleman in a tattered coat. His eyes, set in a deeply lined face, broadcast extreme pain. He’s clearly lived a hard life, and the image implicitly asks: Is there a way out of poverty?

Born to a Jewish father in Austria (she was later baptized), Model was, according to exhibit notes, “drawn to the margins of society.” Her 1945 portrait “Albert-Alberta, Hubert’s 42nd Street Flea Circus” was about as marginal as one could get, focusing on a chubby, smiling, cross-dressing man. Making no attempt to pass as a female, he proudly wears lipstick and high heels, part of an outfit that would be somewhat provocative even on a woman. He smiles gleefully and unashamedly at Model’s camera. This was real life, not the sanitized images that were, and still are, seen in popular magazines.

In a similar vein, N. Jay Jaffe’s “May Day, New York 1948″ focuses on another group challenging convention, foreshadowing the anti-war movement of the 1960s with its depiction of a march through the city’s streets.

Jerome Liebling's "Butterfly Boy, New York," shot in 1949, is typical of Photo League style in its interest in an underrepresented minority. (Courtesy of the Contemporary Jewish Museum)

Jerome Liebling’s “Butterfly Boy, New York,” shot in 1949, is typical of Photo League style in its interest in an underrepresented minority. (Courtesy of the Contemporary Jewish Museum)

Photos such as Morris Engel’s “Harlem Merchant” underscore how difficult it was to eke out a living, showcasing those pushed to the periphery of American society. (Not all the League photographers had Jewish roots: Other featured artists include Rosalie Gwathmey, whose “Shout Freedom” portrays racial inequality in the American South.)

Not all of the photographs contain social messages. Some exist simply to capture a moment and preserve it. Arthur Leipzig’s “Chalk Games, Prospect Place, Brooklyn 1950,” beautifully recalls a time when children played in the streets, while Walter Rosenblum’s “Girl on a Swing, Pitt Street, New York, 1938,” is a hauntingly stark image of a young girl in a neighborhood park, set against the gargantuan Williamsburg Bridge looming over her.

Still, the exhibition is largely a reminder of social activism’s rich history, acknowledging the important role that American Jews have played in many key causes. It also includes a seven-minute excerpt of the recent documentary “Ordinary Miracles: The Photo League’s New York.” The first feature-length film to tell the Photo League’s story, the documentary is full of evocative archival footage carefully juxtaposed with recent interviews of surviving members.

Through the Photo League, Grossman weighed in on an array of social and political issues. After seeing the League crumble under the weight of false accusations, he died of a heart attack in 1955, and for years was largely ignored.

“The Radical Camera” redeems him, giving him the recognition denied during his lifetime.