ROME (CNN) -- Pope Benedict XVI's former butler declared himself innocent Tuesday of a charge of aggravated theft in connection with leaked documents -- but said he had abused the pope's trust.

Paolo Gabriele has previously admitted taking hundreds of secret papers from the pope's personal apartment and passing them to an Italian journalist.



Gabriele asserted his innocence Tuesday when he was asked by his lawyer about the theft charge, according to a pool of selected journalists allowed into the courtroom. The Vatican penal system does not require a formal plea.

But, he said: "I feel guilty of having betrayed the trust that the Holy Father gave me."

The former butler added that he felt he was "the closest layman to the pope."

Corruption claims resulting from the publication of a book based on the leaked materials rocked the Catholic Church hierarchy and could even affect who becomes the next pope.

Testifying Tuesday, Gabriele told the presiding judge, Giuseppe Dalla Torre, that he had received no money in exchange for the papers, according to the journalist pool.

The accused said he did not believe he was the only person to give "news" to the press, but also said that he had "no accomplices."

Computer technician Claudio Sciarpelletti, who worked in the Vatican's secretariat of state, is accused of complicity in the crime. The court will try him separately, once the former butler's trial is finished.

If convicted of aggravated theft, Gabriele could face up to eight years in an Italian prison, although it is possible the pontiff could choose to pardon him. Sciarpelletti would face a shorter prison term of only a few months if found guilty.

Speaking about his detention earlier this year, Gabriele told the court that when he was first arrested he was put in a cell so small he couldn't open his arms out to their full extent.

He was later moved to another, larger cell, Gabriele said. However, in this cell, where he was held for 15 to 20 days, the light was kept on 24 hours a day with no means for him to turn it off, he said. Gabriele said his eyesight had been damaged as a result.

The Vatican prosecutor's office has opened an investigation into his claims of poor treatment in detention.

But Jesuit Father Federico Lombardi, head of the Holy See media office, told reporters in a briefing after the court session that the cells used by the Vatican meet international standards.

Lombardi also suggested that the allegations by Gabriele's defense lawyer that his client had been inhumanely treated seem questionable, since they were only coming out now.

Also Tuesday, the pope's personal secretary, Monsignor George Gaenswein, testified that he never "had any reason to doubt" Gabriele.

More witnesses will be heard in the case Wednesday.

Gabriele, wearing the same gray suit he had on for Saturday's initial hearing, appeared more relaxed Tuesday, smiling, closing his eyes briefly and intermittently chewing either gum or candy, according to the journalist pool.

In the previous hearing Gabriele had appeared pale as he sat largely expressionless in the courtroom.

Both sessions were held under closely controlled conditions, with only a handful of approved reporters allowed to attend. They were required to brief other journalists.

On Saturday, the admitted journalists were made to hand over their own pens in exchange for Vatican-issue ones in case any contained concealed recording devices.

Gabriele's family did not attend either session.

The court revealed in the initial hearing that Vatican investigators had seized 82 boxes of evidence from Gabriele's apartments in Vatican City and Castel Gondolfo, a small town near Rome.

Authorities also had uncovered in Gabriele's apartment in Vatican City a gold nugget and a check made out to Pope Benedict XVI for 100,000 euros, as well as an original version of Virgil's Aeneid from 1581, the court said.

Gabriele's lawyer, Christiana Arru, filed objections concerning the admissibility of evidence Saturday, including the results of a psychological exam conducted without the presence of his lawyer and footage gathered via a hidden camera, some of which the court accepted.

The former butler's case is thought to be the most significant ever heard in the Vatican City courthouse, which has handled mostly petty theft cases in the past.

A Vatican legal expert, Cardinal Velasio De Paolis, said in an interview published Sunday in Italian newspaper La Repubblica that popes in the past have typically granted pardons in the face of sincere confessions and repentance.

A prosecutor in the case said in a report last month that Gabriele had acted out of a desire to combat "evil and corruption everywhere in the Church."

"I was certain that a shock ... would have been healthy to bring the church back onto the right track," Gabriele is quoted as saying by the prosecutor, Nicola Piccardi.

The Vatican City State penal code for proceedings involving its citizens is based on the Italian penal code of the second half of the 19th century. Dalla Torre will lead the debate in the courthouse, located behind St. Peter's Basilica, and question the defendant directly.

Prison terms handed down by the court are served in the Italian prison system, under an agreement between the Vatican City State and Italy.

Gabriele was arrested in May, following a top-level Vatican investigation into how the pope's private documents appeared in the best-selling book "Sua Santita" ("His Holiness"), by Italian journalist Gianluigi Nuzzi.

The Vatican called the publication of his book "criminal" when it was released in Italian.