GWEN IFILL: Now, The details of last summer's mass killing in Norway play out in court.
We begin with a report from Martin Geissler of Independent Television News in Oslo.
MARTIN GEISSLER: This was the day Anders Breivik had been waiting for, his chance to defend the seemingly indefensible, to share with the world the beliefs that drove him to commit mass murder.
He seemed to be relishing the moment, seeking eye contact with the public benches. He had spent years preparing for this platform and killed 77 people to get it. But as he was called to take the stand, the cameras were turned off.
The court's authorities have a balance to strike here. While they want to limit Anders Breivik's exposure, they won't censor him. So, while we can report on what was said inside this courtroom, we can't broadcast the pictures.
For more than an hour, he read from a 13-page statement, painting himself as a national hero protecting the white native Norwegian. "Brutality is not necessarily evil," he said. "It depends on your motivation. I was trying to avert a major civil war in Europe. My actions were based on goodness."
He said many others shared his opinions, but their voices are suppressed. "The last time there was real democracy in Europe," he said, "was when Hitler came to power."
Of his victims, he said, they were not innocent non-political children. "I executed these people to strike at our multicultural ideology. We can't wait any longer," he said. "I'm the first drop of water signaling a coming storm."
Breivik said he toned down his rhetoric out of respect for the victims, many of whose families were sitting just feet away. Breivik's every move and every word are being studied by a panel of psychiatrists in court. His mental state is central to this case and will determine how he's punished. He'll stay on the stand under cross-examination, which could last another four days.