Here's What's Happening:
The penalty phase of convicted Boston Marathon bomber Dzhokhar Tsarnaev began Tuesday in federal court.
On April 8, Tsarnaev was convicted on all 30 counts for his role in April 2013 attacks with his brother Tamerlan. Seventeen of the 30 charges carry the possibility of the death penalty.
During the criminal trial, Tsarnaev's lawyers admitted that their client was responsible for the 2013 attacks and called only four witnesses. The defense is expected to make a more comprehensive argument for sparing Tsarnaev's life during the penalty phase.
After the guilty verdict, several bombing survivors and family members of victims spoke out about what sentence they feel Tsarnaev deserves. The parents of Martin Richard, the youngest person killed in the attack, published an open letter in the Boston Globe asking the government to drop the death penalty.
The U.S. attorney for the District of Massachusetts said last week that she is taking every victim's opinion into consideration. She gave no indication that the government would drop its pursuit of a death sentence.
The penalty phase is expected to last four weeks. The only sentences that the jury can decide between are life without parole or death.
The last witness called to testify on Tuesday was Nicole Gross, who suffered severe leg injuries as a result of the blast.
Gross was at the finish line to support her mother, who was running in the marathon. She began to break down as she identified her husband, Michael, and her sister in a photo before the bombing.
Gross' husband was standing next to Tamerlan Tsarnaev in one of the photos shown in court. Gross said her leg was "blown open" by the bomb and it felt like her foot was hanging by threads. She said she screamed for "somebody to save me."
Gross also recalled being angry when someone took a photo of her at the time. She saw her husband standing there but she was unable to speak to him. She also saw her sister on the ground. Her legs were wrapped in tourniquets and her left leg was broken and pointed in the wrong direction, Gross said.
"I just kept feeling helpless and alone. I couldn't find my husband or mom," she said as she described her experience at the hospital, where she underwent at least 10 surgeries.
As a result of the blast, Gross ultimately suffered extensive damage to her legs and eardrums.
Gross added that her sister has had 20 surgeries, her leg was amputated below the knee.
William Campbell Jr. was called next to testify about the death of his daughter Krystle.
He said, Krystle was "the light of my life." He called her a "perfect young lady," but she was "no girly-girl."
Campbell Jr. said his daughter helped him get out of bed during his back trouble. "I was ready to give up...she got me moving," he said.
He said she always made him happy and called him everyday. She was also very close to her mother, and they were like buddies, Campbell Jr. said. He also spoke about her close relationship with his grandson "little Billy" who would ask "where's Aunty" whenever she was running late.
He said he was home watching the marathon on TV and felt something "didn't feel right" when he heard news of the explosion.
The jurors were moved to tears as Campbell Jr. cried while talking about the confusion with her identity at the hospital. He told doctors to take her leg, and do whatever they could "to save my baby" before he realized it wasn't her.
The jurors were shown family photos again, including one from Krystle's first birthday where she sat beaming in her high chair. They saw a photo of Krystle in a cream dress at her high school prom as her father described her as a popular girl who had many friends.
The next government witness was William Campbell III, the brother of Krystle Campbell, who died in the attack.
Campbell said his earliest memories of Krystle were of playing video games and fighting over the TV remote as kids. He said she was a "hard worker" and paid her own way through college. She held jobs since she was 14 years old, he said.
"My favorite memory of her is more of a feeling; I just always knew I had someone there for me when I was with her," Campbell said.
He last saw her the Saturday before the marathon when they went to the mall with his 6-year-old son. When he heard about the bombings that Monday, he said he had a "mini panic attack" and tried to call her, but there was no answer. He said a nurse called him from Krystle's phone to tell him she was one of the victims. The nurse told him Krystle was OK and would recover, but it turned out the hospital mistook her identity with that of her friend Karen Rand, who was at the marathon with her.
Hours later, Campbell was told his sister was dead.
He said he had a hard time dealing with her death: "You don't know what to say, don't know what to do."
Two years later, not a day goes by when the family doesn't think of her, Campbell said. "The hardest thing is not being able to pick up the phone and call Krystle."
The government showed the jurors childhood pictures of the siblings where Campbell was dressed in a tuxedo and Krystle was in a bright blue dress at a wedding. They also showed a photo of their parents' surprise 25th wedding anniversary party, which Krystle organized. Campbell narrated short, sweet stories behind each photo of Krystle and their family, eliciting laughter in the courtroom.
Next on the stand is bombing survivor Gillian Reny, whose leg was severely wounded in the blast.
Reny had been to the marathon at least 10 times and was watching her sister run in 2013.
She described the moments after the bombing. It was "complete, utter chilling silence," she said, and then "chaos ... like I hope to never see again."
Reny broke down on the stand as she described her injuries. "I looked down at my legs and there was so much blood. My tibia had been snapped in half." Jurors teared up as well listening to Reny's testimony.
"It was horrifying to look down and see that that was your own body," Reny said.
She said that there were bodies and blood everywhere. "The pain that I was experiencing is something that I wouldn't wish on anyone in a million years."
She cried again as she said, "I didn't know that you could be that injured and still survive."
Reny said her father followed the instructions of an army vet nearby and used his belt as a tourniquet. She said she expected to pass out from the pain but remained conscious. "Guess movies aren't accurate in that sense."
Like Corcoran, Reny was also made to identify herself and her family in a series of graphic photos from the blast.
An amateur video of the blast is played, showing Reny on the ground surrounded by bloodcurdling screams.
A baby can be heard wailing along with screams of women and children. Reny avoided the video and cried on the stand as her mother cried in the front row.
The jurors were shown images of Reny and her mother cradling each other on the sidewalk surrounded by pools of blood and shrapnel. Reny's mother appeared to be protecting her daughter in the photo.
"They were able to salvage my leg," said Reny, who added that she was unsure of how functional it would be after undergoing a long surgery. She said that she still had chunks of her leg missing.
The government called its first witness, Celeste Corcoran, who lost both her legs in the attack.
Corcoran, who worked as a hairstylist, said she went to the Boston Marathon in 2013 to watch her sister running in her first marathon. The jurors were shown pictures of Corcoran with her husband Kevin and their daughter, before the bomb went off.
Corcoran said she was determined to see her sister cross the finish line.
"Then our whole world exploded," she said, adding that she remembered every single detail because she did not pass out.
She described being thrown in the air and landing hard. "It was like this deafening silence," she said, remembering how she was choking and spitting and that there were bloodcurdling screams and blood everywhere. Debris was falling from the sky, she said.
"I just remember lying there ... thinking, like, What was that?" She recalled how she couldn't sit up. "I just remember seeing so much blood where my legs were."
She remembered thinking, I want it to be five minutes ago.
She said her husband stroked her hair and told her she was going to be OK. He knew it was a terror attack even then, she said.
When she asked him if her feet were still attached to her legs, he said yes.
"There was so much screaming and chaos. I just raised my arms to cover my eyes ... I didn't want to look at anything else," Corcoran said.
She kept thinking, No, no, no, this doesn't happen here, she recalled. Her husband told her he loved her and that she was going to live. He used belts as a tourniquet and told her, "I'm not going to leave."
Inside the medical tent, her top was cut and a number was written on her chest "because they had to get me out fast," she said.
"I remember thinking that I wanted to die," Corcoran said. "I remember thinking that the pain was too much and I wanted to die."
At the hospital, she said she remembered thinking she needed to live for her children. Hell no, I don't want to die. Please don't let me die, she recalled thinking.
After emerging from her surgery, Corcoran said she found out that her daughter Sydney was also at the same hospital and had been hurt in the attack. She shared a hospital room with Sydney for three to four weeks after the blast.
"To see your child in pain and not be able to go to them," Corcoran said as she told jurors how hard it was for her to lie "helpless."
While describing her injuries, Corcoran said she had shrapnel and burns in her body "like a tattoo."
Corcoran said she got a service dog named Sebastian who helps support her as she walks on her prosthetics. When she falls, the dog offers his shoulder to help her get up.
Jurors were shown graphic pictures of the carnage on Bolyston Street. Corcoran identified herself and her daughter lying on the blood-splattered sidewalk. She then described the scars on her daughter's thighs shown in a photo. Corcoran told the jurors the extent of Sydney's injuries. "She had a hole blown through her foot," she said.
The defense did not cross-examine Corcoran, whose graphic testimony brought some of the victims' families to tears in the courtroom.
The government concluded its opening statement with the photo of Tsarnaev showing his middle finger in court.
Tsarnaev "was destined to become America's worst nightmare," Pelligrini said. When Tsarnaev was in court awaiting his arraignment in 2013 he had one more message, she said, showing the jurors a huge photo of Tsarnaev showing his middle finger at the camera in the holding cell. In the photo, a younger-looking Tsarnaev in orange scrubs is also puckering his lips in a kiss.
The U.S. Attorneys office said that the photo will not be released to the public today as it hasn't been entered into evidence yet.
The government emphasized how Tsarnaev "walked alone" down Boylston, "stood alone" behind the Richard family, and "walked off alone" later.
The prosecutor told jurors that Tsarnaev "was and is unrepentant, uncaring and untouched ... by the sorrow he has created." The "origin and lineage" of his radicalization didn't matter, but what matters is his act of terrorism, she said.
AUSA Nadine Pelligrini delivers the opening statement for the government.
The government showed poster-size photos of the four deceased victims of the Boston Marathon bombings. "Now these beautiful faces are memories," Pelligrini said. "You know how Krystle, Lingzi, Martin, and Sean died. Now you need to know how they lived."
Pelligrini said that all the victims' families want is "for them to come home one more time."
She told the jurors that Tsarnaev took the victims away "in the most painful and brutal way possible." She said the government will answer why the death penalty is the "appropriate and just sentence" for Tsarnaev.
Tsarnaev's attorneys will wait until next week to make their opening statement.
Dzokhar Tsarnaev entered the courtroom wearing a gray sweater under a black suit jacket. Bill Richard, the father of 8-year-old victim Martin Richard, was present. He and his wife wrote an open letter asking the government to drop the death penalty against Tsarnaev and grant him a life sentence.
While instructing the jury before the opening statements, the judge told them the the decision regarding the death penalty is left "exclusively to you." He told them they can consider all evidence, including what was presented during the guilt phase of the trial.
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