By Daniel Schweimler
BBC News, Buenos Aires
A trial has begun in Argentina of one of the most notorious figures of the military government in power between 1976 and 1983.
Von Wernich came to court in a bulletproof vest
Roman Catholic priest and former police chaplain Christian Von Wernich is accused of involvement in seven murders and 41 cases of kidnapping and torture.
He escaped prosecution under amnesty laws which were later declared unconstitutional.
Security is tight. More than 100 witnesses have special protection.
Father Von Wernich, 69, appeared in court wearing a bulletproof vest. He seemed calm, almost bored, and said little as a long list of accusations was read out.
He served as chaplain to the Buenos Aires provincial police force, and he is accused of using his office to win the trust of prisoners before passing information to the police torturers and killers who were holding them.
The case is expected to last two months
He is also reported to have attended a number of torture sessions himself and reassured the police that they were doing God's work.
He escaped prosecution after the democratic governments that followed the military passed amnesty laws.
Father Von Wernich worked under a false name in Chile, but investigators tracked him down and he was arrested four years ago.
Those amnesty laws have since been declared unconstitutional and some of those responsible for the killing of an estimated 30,000 people under military rule between 1976 and 1983 are finally being brought to trial in Argentina.
But witnesses have been threatened and one, Julio Lopez, disappeared after giving evidence at a trial last year and has not been seen since.
The trial is expected to last two months.