The trial began Saturday for butler Paolo Gabriele, who is charged with aggravated theft for allegedly giving hundreds of secret papers from the pope's personal apartment to an Italian journalist.
The judges rejected evidence from questioning conducted by three cardinals at the pope's behest, the Los Angeles Times reported Saturday. The cardinals interviewed their peers in an investigation into Vatican infighting, results of which were intended for the pope and not to be made public or part of the trial.
Meanwhile, the judges also ruled Saturday that aiding and abetting charges against Claudio Sciarpelletti would be handled in a separate trial. Sciarpelletti, a former computer technician who worked in the Vatican's secretariat of state, allegedly helped Gabriele in the crime. If found guilty, he faces a prison term of a few months.
Gabriele has admitted leaking faxes, letters and memos, including some from a high-ranking church official expressing concerns about corruption within the Vatican.
Prosecutors said last month Gabriele acted out of a desire to combat "evil and corruption everywhere in the church."
If convicted, Gabriele could be sentenced to as many as eight years in prison.
The trial was adjourned until Tuesday, the Times reported.