you don't say... 'infighting' aka eating their own doubled down.. as in.. believers first then themselves.. fkn' patriarchal fraud, lies, waste and abuse~ megh...
The former butler is serving his sentence in a special detention room inside the Vatican's police station, amid talk that he may be pardoned by Pope Benedict XVI.
Mr Sciarpelletti, 48, handled secret communications in Secretariat of State, the nerve centre of the Roman Catholic church, the BBC's David Willey reports from Rome.
Investigators say he helped Gabriele leak the confidential documents to the Italian media.
Mr Sciarpelletti was arrested briefly in May, but then released after the Vatican said he played only a "marginal" role in the scandal.
Interest in the case centres on who the witnesses called to give evidence may be, our correspondent says. A senior cleric and two top Vatican security officials are expected to be called.
It is thought the trial may throw a light on the extent to which other Vatican employees, including clerics, may have been involved.
The Vatican has always insisted Gabriele acted alone, but some believe he was part of a wider conspiracy to publicise sensitive information.
Much of the stolen information ended up in a best-selling book by journalist Gianluigi Nuzzi about corruption, scandals and infighting at the Vatican.
Gabriele confessed to taking the papers, but said he believed the Pope was being manipulated, and that he hoped to reveal alleged corruption at the Vatican.
The Vatican authorities are limiting press access to Mr Sciarpelletti's trial and no TV cameras are to be allowed in court, our correspondent says.