However, Cardinal Tarcisio Bertone, speaking to Latin American journalists at the Vatican before departing for Mexico, expressed doubt that the prospect of excommunication -- the harshest sanction imposed by the Roman Catholic -- would have much influence on killers devoid of "ecclesiastical conscience," the Los Angeles Times reported.

Bertone said Monday drug gang violence represents "the most hypocritical and terrible way of murdering the dignity and personality of today's youth."

"Certainly, excommunication is a very harsh deterrent that the church has used to deal with the most serious crimes in its history, from the very first centuries," Bertone said. "But I should observe that excommunication is a punishment that touches only those who have some form of ecclesiastical conscience, an ecclesiastical education."

Excommunicated Catholics are forbidden from receiving church sacraments or joining other Catholics in public worship.