The secret conclave that elected Pope Leo head of the Catholic Church in May 2025 was interrupted when one of the 133 cardinals involved was found carrying a cellphone, a massive security breach, a book released on March 1 revealed.
As the clerics were preparing to take their first vote inside the Vatican’s Sistine Chapel, which was fitted with jamming equipment to prevent outside communications, security officials picked up the signal of an active mobile connection.
The cardinals stared at each other incredulously, then one of the older clerics discovered he had a phone in his pocket and handed it over, according to The Election of Pope Leo XIV, a new book by two long-time Vatican correspondents.
The book does not name the cardinal or suggest he had any motive for keeping his phone, saying the moment left him “disoriented and distressed”.
Security breach was ‘better than fiction’
The scene was “unimaginable even for a film and never before seen in the history of modern conclaves”, wrote authors Gerard O’Connell and Elisabetta Pique.
One such film, the 2024 hit Conclave, imagined a tangled web of intrigues during the fictional selection of a pontiff. The unprecedented discovery of a phone in 2025 was in its own way more startling than anything portrayed in that movie, O’Connell told Reuters. “Reality (was) better than fiction,” he said.
Clerics taking part in a conclave take a vow not to communicate with the outside world and surrender their phones and all other communication devices for the duration of the proceedings, which can last for days.
Hellbound and Down 