VATICAN CITY — Pope Benedict XVI on Monday changed the rules of the conclave that will pick his successor, allowing cardinals to move up the start date if they all arrive in Rome before the usual 15-day waiting period after the end his pontificate.
Benedict signed a legal document, issued Monday, with some line-by-line changes to the 1996 Vatican law governing the election of a pope. It was one of his last acts as pope before stepping down at 8 p.m. Thursday.
The date of the conclave’s start is important because Holy Week begins March 24, and Easter Sunday is March 31.
In order to have a new pope in place for the church’s most solemn liturgical period, he would need to be installed by Sunday, March 17. That is a tight timeframe if a conclave were to start on March 15, as previous rules would require.
Also Monday, Benedict decided that the contents of a secret investigation into the 2012 leaks of Vatican documents won’t be shared with the cardinals ahead of the conclave.
Benedict met Monday with the three elderly cardinals who conducted the probe and decided that ‘‘the acts of the investigation, known only to himself, remain solely at the disposition of the new pope,’’ a Vatican statement said.
Speculation has been rife in the Italian media that the three cardinals — Julian Herranz, Jozef Tomko, and Salvatore De Giorgi — would be authorized to share the information with fellow cardinals before the conclave.
That assumed the cardinal electors would want to know details about the state of dysfunction in the Vatican bureaucracy and on any potentially compromised colleagues before possibly voting one into office.
Benedict appointed the three men last year to investigate the origins of leaks, which revealed petty wrangling, corruption, cronyism, and even allegations that senior Vatican officials conspired to reveal a prominent Catholic newspaper editor was gay.
The pope’s butler was convicted of aggravated theft in October for having stolen the papers and given them to a journalist who then published them in a blockbuster book.
The three cardinals cannot share the full contents of their investigation, but it’s unclear if they could give subtle hints about potential papal candidates to the electors. The Vatican’s assertion that only the pope knew the contents of the dossier was a clear message to readers of Italian newspapers, which have run several articles purporting to know the contents of the report.
On Sunday the pope repeated that he plans a life of prayer and contemplation in his retirement, but will continue to service the church as he can.
“This doesn’t mean abandoning the church,’’ the pope said. “On the contrary, if God asks me. This is because I can continue to serve with the same dedication and the same love which I have tried to do so until now, but in a way more suitable to my age and to my strength.’’