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Boston Bombing Trial: Tsarnaev Penalty Phase Focuses on Victims of Blasts

“It’s still a huge loss,” Andrew Collier said of his brother’s killing.
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/ Source: NBC News

The brother of Sean Collier, the campus police officer killed three days after the attack on the Boston Marathon, remembered him Wednesday as having a strong moral compass — down to a belief that “you can’t kill a bug.”

Andrew Collier testified on the second day of the penalty phase of the trial of Dzhokhar Tsarnaev, who prosecutors say should be put to death for planning and executing the marathon bombings with his brother.

“It’s still a huge loss,” Andrew Collier said. “It is something that will affect my family for the rest of our lives.”

Sean Collier, an MIT police officer, was killed April 18, 2013, during the manhunt for the marathon suspects. His boss, MIT Police Chief John DiFava, remembered Collier as one of the best officers he has seen in decades of law enforcement.

“He always did the right thing,” DiFava testified. “Peer pressure did not work with Sean.”

Jurors also heard from Jinyang Zhao, who described herself as an aunt to Lingzi Lu, a Boston University graduate student who was killed in the attack. She says she testified because Lu's parents are too distraught to leave China. She remembered Lu as bubbly, smart and determined.

"I feel she was kind of a beautiful nerd," Zhao said. "Beautiful but kind of nerdy, too."

They last spoke the Friday before the bombing, when Lu told Zhao she had a lot of studying to do, Zhao recalled. She said that her mother wanted Lu to be buried in Boston.

"She felt she was part of Boston, part of the city, so she felt she should be here," Zhao recalled.

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On Tuesday, a federal prosecutor said that Tsarnaev was "determined to be America’s worst nightmare" and was unrepentant.

The defense, arguing for life in prison, is expected to begin presenting its case next week.

As they did on Tuesday, federal prosecutors called witnesses who described horrific scenes of blood and chaos after the blasts.

Adrienne Haslet-Davis, who was watching the marathon with her husband from Boylston Street, broke down on the witness stand as she told of dragging herself on her stomach into a restaurant. She said her leg was covered in blood.

Later, at a hospital, “I just kept screaming I was a ballroom dancer,” she said.

Haslet-Davis said she called her parents and said, “I’ve been in a terrorist attack and Adam is dead.” He survived, and has since admitted himself to a mental health facility for veterans, she said.

Another witness, Eric Whalley, described an “almighty boom” from one of the blasts. He said he had had 20 to 25 surgeries, lost sight in one eye and still has a ball bearing lodged in his brain because doctors have decided it is too risky to remove it.