TORONTO – Just weeks after the Sundance premiere of “The Infiltrators,” Cristina Ibarra and Alex Rivera’s documentary about conditions inside a Florida immigration detention center, one of the film’s subjects, Claudio Rojas, was detained by U.S. Immigration and Customs Enforcement (ICE) agents and deported back to his native Argentina.

Rojas, who spent 19 years living in the U.S., had been an inside source for a documentary that exposed abuses inside the Broward Transitional Center, a for-profit institution that has detained hundreds of immigrants without trial. His ordeal served as a timely reminder of the countless lives still imperiled by the recent migrant crisis — a historical event that’s offered raw material for a number of documentaries screening at the Hot Docs Canadian Intl. Film Festival this year.

“It’s an ongoing theme that’s more important than ever,” said Shane Smith, Hot Docs director of programming. “Filmmakers are doing a great job of getting below the surface and looking not only at the story that they’re telling, but the systemic issues that give rise to those stories… It’s shining a light not only on the personal, immediate story, but on how we got here.”

One example is Suzan Beraza’s “Massacre River,” which examines the fallout of a 2013 constitutional court ruling in the Dominican Republic that effectively rescinded citizenship rights for more than 200,000 Dominicans of Haitian descent. Against a backdrop of rising populism and the spread of mob violence, Beraza uses one woman’s struggle to prove her birthright as a way to look at “how systems and politics and agendas are being used to turn us against each other,” according to Smith. “It’s painting on a broader canvas, it is a bigger-picture story.”

Europe’s migration crisis was the starting point for Nuno Escudeiro’s “The Valley,” which follows citizens along the border between France and Italy who embrace civil disobedience to help migrants attempting to cross perilous routes through the French Alps. As they offer the asylum seekers food, shelter and legal assistance, the volunteer groups increasingly find themselves pitted against the authorities in a battle over basic rights.

“The whole story became about the consequences of closing the border… and how a political decision can impact the lives of so many people,” said Escudeiro. “From the beginning, I had this feeling that I want to contribute in a way that helps us see this as a historical moment, and that we as a society, we can say something. We can mold our way, and how we’re going to be remembered in history.”

Another film making its world premiere in Toronto this week was “The Guardian of Memory,” Marcela Arteaga’s powerful evocation of the lives of Mexicans fleeing the Juarez Valley — a region straddling the U.S. border caught in the crossfire between a brutal drug war and an epidemic of state-sponsored violence. The film centers on Carlos Spector, an immigration lawyer from El Paso who fights to win political asylum for Mexicans fleeing violence, and the asylum-seekers who have come to him for help.

“In Mexico, we know all about the Central American immigrants crossing thorough Mexico, and all the atrocities that Mexican authorities are doing to them. But nobody in Mexico knows about the Mexicans doing exactly the same, and seeking asylum in the United States,” said Arteaga. “When these people leave Mexico, they are forgotten. Because here they are treated as traitors, and in the United States as criminals.”

She added: “Even in Mexico, they become statistics, not human beings that have suffered.”

The human toll of the refugee crisis will take years to tally, but documentary filmmakers are making important contributions by sharing the voices and stories of those affected. Their stories don’t end on screen: this week festival organizers have been working with the producers of “The Infiltrators” to secure a tourist visa for Rojas, so that he can attend the film’s screenings in Toronto. “These are real-world impacts that the filmmakers are having,” said Smith.