Knowledge of clergy sex abuse is widespread on the mainland of the United States. But it has long been a secret in the small, overwhelmingly Roman Catholic U.S. territory of Guam.

Washington-based investigative reporter Michael Biesecker, working with Atlanta-based enterprise photographer David Goldman and Seattle video journalist Manuel Valdes, helped to puncture that veil of silence when AP examined thousands of pages of court documents in lawsuits brought by abuse victims and then conducted extensive interviews.

Through careful and thorough reporting, the team detailed a pattern of repeated collusion among predator priests, with abuse that spanned generations and reached all the way to the top of the territory’s church hierarchy, ruled over by then-Archbishop Tony Apuron, who himself had been accused of the rape of a 13-year-old choir boy when Apuron was his parish priest. Rapes and other abuses continued as Apuron rose through the church ranks to become the territory’s prelate, his accusers allege.

Biesecker read case files for each of the 223 lawsuits filed by abuse survivors, tracking the number of complaints against each of the accused and noting similarities. From there, he worked with lawyers to set up on-camera interviews with seven key survivors.

On the island, Goldman conducted additional interviews with at least five more for a series of powerful portraits showing each person with a picture of himself at around the age when they say they were abused by Catholic clergy. Valdez captured the anguish of the survivors, many of whom told them on camera for the first time, breaking down in tears. Freelance reporter Grace Garces Bordallo provided invaluable local knowledge and helped with fact-checking. The package included a text and video explainer on how deeply Catholicism is ingrained in daily life on the island.

The team tracked down a priest accused of abuse in Hawaii. They found him living in a home with children and interviewed him on camera. They also traced Apuron to an address in New Jersey, although residents of the home denied knowledge of him. (Apuron continues to deny the accusations. However, a secret church trial last year found him guilty of sex crimes against children, removing him from his public ministry and effectively exiling him from Guam.)

Biesecker came to realize the extent of clergy abuse lawsuits on Guam almost by accident. He was researching federal court records on abuse by scoutmasters who were also priests when he saw the high number of lawsuits on Guam. Digging further, he learned more about the accusations against the archbishop and saw a broader story.

In a series of phone calls, Biesecker convinced a lawyer representing most of the victims to provide access to her clients, if they chose to speak with him. Biesecker then worked to secure interviews with key survivors whose accounts he had read about in the lawsuits, including the archbishop’s own nephew.

The care and sensitivity of the reporting team were key to the project’s power.

Having conducted interviews with survivors of violence and sexual assaults earlier in his career, Biesecker knew that pressing the victims too hard to talk about painful childhood experiences could retraumatize them. Instead, he often began by asking about their home villages, their families and other more benign topics before slowly turning the conversation to what the priests had done.

Biesecker spoke very little during these encounters, encouraging survivors to tell their stories at their own pace, revealing only as much as they felt comfortable. Eventually, some of the survivors chose to talk on camera about memories so painful they had repressed them for decades, not even sharing the troubling details with their parents or spouses. After the interviews were over, Biesecker went back to them days or weeks later to make absolutely sure that the survivors were comfortable with him writing about such deeply personal details. They all agreed.

“To see my story told in this way gives me a lot of peace, that I have a purpose,” said Walter Denton, a former U.S. Army sergeant and survivor of abuse nearly 40 years ago.

For telling a sensitive and little-known story of systemic clerical abuse dating from the 1950s to as recently as 2013, Biesecker, Goldman and Valdes share AP’s Best of the Week award.