He had the trust of Pope Benedict XVI and the cardinals, monsignors and priests who run the Roman Catholic Church. And because of his privileged position as papal butler, he had access to their deepest secrets: confidential letters, memos, financial reports.

From under Benedict's nose, Paolo Gabriele used the photocopier in the small office he shared with the two papal secretaries that adjoined the pope's library, studio and chapel — and, he says, started copying them all.

At first he kept the documents to himself. Then he found a journalist he trusted, and the intrigues and injustices he saw around him spread around the world in the gravest Vatican security breach of modern times.

A three-judge Vatican tribunal on Saturday will decide whether Gabriele is guilty of aggravated theft, accused of stealing the pope's private papers and leaking them to journalist Gianluigi Nuzzi, whose book "His Holiness: Pope Benedict XVI's secret papers" became an immediate blockbuster when it was published in May. Gabriele has pleaded innocent, claiming he never took original documents, though he said he was guilty of "having betrayed the trust of the Holy Father, whom I love as a son would."

From court documents, trial testimony and the book itself, the anatomy of the scandal has taken shape: They describe how a 46-year-old father of three, said by court-ordered psychiatrists to be unstable, desperate for attention and with illusions of grandeur, came to consider himself inspired by the Holy Spirit to expose the Vatican's dirty laundry for the sake of saving the church. They demonstrate how he instigated an unfathomable Hollywood-like plot to sneak the documents out of the Apostolic Palace under the cover of darkness to a waiting journalist outside the Vatican walls, who then exposed them on TV and in the most talked-about book of 2012.

Gabriele himself told the court this week that he became increasingly "scandalized" when, as he would serve Benedict his lunch, the pope would ask questions about issues he should have been informed about. That suggested to Gabriele that the pope was being intentionally kept in the dark by his advisers.

"I had a unique and privileged occasion to mature the conviction that it's easy to manipulate someone with decision-making power," Gabriele said of the pope. "With the help of others like Nuzzi, I thought I could help things be seen more clearly," he told prosecutors in a July 21 interrogation.

Gabriele told Nuzzi that he started copying documents sporadically soon after Benedict became pope in 2005, and then in earnest in 2010 and 2011, when the No. 2 Vatican administrator began complaining about a smear campaign launched against him for having uncovered corruption and waste in running the Vatican City state.

In his testimony, Gabriele almost boasted that he would copy the letters in broad daylight, during his 7 a.m.-2:30 p.m. shift, while Monsignor Georg Gaenswein and the other papal secretary, Monsignor Alfred Xuereb, were at their desks facing his. He was free to sort through the mail that would come in daily to the office inboxes, even documentation that was on Gaenswein's desk.

"The photocopier was in the corner, on the opposite side of the office," Gabriele told the court as his lawyer handed out a floor-plan of the shared space. "I did it while I was in the office, since I was free to move around and didn't have any wicked aims. I did it calmly, even in the presence of others."

At the same time, Gabriele would also discuss Vatican problems with any number of trusted acquaintances he would run into on his walk home from the palace. On foot, the walk should take three to four minutes, he said, but sometimes he didn't get home until 4 p.m. because he would be stopped by so many highly-placed people who wanted to speak to him.

He named names, including cardinals and monsignors. But in his testimony this week, Gabriele insisted he had no accomplices, recanting statements to prosecutors that his plot had been "suggested" to him by others.

Once home in the Vatican City apartment he shared with his wife and three children, Gabriele would file the papers away, "hidden" — police would later say — in between hundreds of thousands of pages of Internet research on Freemasonry, secret service units, Christianity, Buddhism and yoga. He filled a floor-to-ceiling armoire with the documentation in the study near his children's' PlayStation. A dining room cabinet held the rest.

"'See how much I like to read and study,'" Vatican police officer Stefano De Santis quoted Gabriele as telling the four officers who searched his home May 23, the day Gabriele was taken into police custody.

In all, it took 82 moving boxes to cart out all the documents they found, though police said only about 1,000 pages were pertinent to the investigation. Police and Gaenswein have said that — contrary to the butler's claims — they also contained original documents, obvious because of the seals, stamps and internal processing codes used in the Vatican.

Some bore the pope's own handwriting, including with the word "destroy" written at the top in German, police told the court.

It was Gaenswein who found the "gotcha" documents that pointed him to the culprit: three letters reproduced in Nuzzi's book that he said had never left his office.

Other documents had come from other Vatican congregations, so they could have been leaked at any point along the internal mail chain. These three, though, were addressed to Gaenswein: one from Italian TV host Bruno Vespa with a check for €10,000 and a request for a private papal audience; another from a Milan banker also containing a check; and an email from the Vatican spokesman that Gaenswein had printed out.

"These three didn't leave the room," Gaenswein testified. "This was the moment I started to have doubts."

He convened a meeting of the tiny papal family on May 21, a day after Nuzzi's book came out: Gabriele, Xuereb, the four consecrated women who tend to the papal household, and Birgit Wansing, who transcribes the pope's tiny handwriting. Cristina Cernetti, one of the women, testified she knew it was Gabriele because she could "exclude everyone else" in the papal family.

Gabriele denied he was the leaker that day. Two days later, Gaenswein again convened the papal family to tell Gabriele he was suspended. A few hours later, he was in a Vatican jail cell.

Gabriele has denied to prosecutors taking any originals, insisting he only made copies. And he has denied having ever seen a nugget believed to be gold and a check for $100,000 made out to the pope that police said were found in his apartment. In their testimony, police were unable to say where exactly in his study they found the items.

Nuzzi has all but confirmed Gabriele was his main source, sending him a good luck Tweet at the start of the trial and telling The Associated Press on the eve of the first hearing that he hoped the testimony would "unveil the motives and convictions that compelled Paolo Gabriele to bring to light documents and events described in the book."

The handoff of documents from Gabriele to Nuzzi was something out of Hollywood.

Nuzzi wrote that he first met with his source, code-named Maria in the book, in January 2012. The first meeting was a test of whether Nuzzi could be trusted. Another meeting began with a long drive around Rome to ensure they weren't being followed. Finally, there was a nighttime encounter in an unfurnished apartment, with a single chair in the living room where his source was sitting — in which "Maria" began spilling secrets.

In all, he said, the security precautions were more excessive than those used by Mafia turncoats he has interviewed. In one meeting, Maria turned up empty handed. Nuzzi recounted that his source then took off his jacket and turned around: There were 13 pages taped to his back.

Gabriele made copies of the documentation he gave to Nuzzi and gave them, in a box with the papal seal on it, to his confessor between February and March, court records show. The priest, identified by Gabriele only as Padre Giovanni, told prosecutors he burned the documentation soon after, knowing that it had been acquired illicitly.

Gabriele said he had made the copies because he knew he would eventually have to pay for what he had done, and wanted first to absolve himself spiritually.

"When the situation degenerated, I soon realized that I would need to face justice in some way," Gabriele testified.

Gabriele faces four years in prison if convicted, though a papal pardon is widely expected.

The next step plays out Saturday.


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