Pope Benedict, accused by victims' lawyers of being ultimately responsible for a cover-up of sexual abuse of children by priests, cannot be called to testify at any trial because he has immunity as a head of state, a top Vatican legal official said on Thursday.

The interview with Giuseppe dalla Torre, head of the Vatican's tribunal, was published in Italy's Corriere della Sera newspaper as Pope Benedict began Holy Thursday services in St Peter's Basilica and Catholics marked the most solemn week of the liturgical calendar, culminating on Sunday in Easter Day.

The pope did not refer in his sermon to the crisis of confidence sweeping the Church as almost daily revelations surface of sexual abuse of children in the past, accompanied by allegations of a cover-up.

More...