Tsarnaev Not Expected to Take Stand, Officials Say

Boston Marathon bomber Dzhokhar Tsarnaev is not expected to take the stand in the defense's effort to spare his life, according to federal officials briefed on the initial witness list.

The defense could change its mind later in the course of the penalty phase of Tsarnaev's trial, but as for now he is not scheduled to face the court, whose audience has included many of his surviving victims and the families of the dead.

The penalty phase of the Boston bombing trial begins today, following Tsarnaev's conviction on all 30 counts related to the April 2013 bombing. The twin explosions detonated at the finish line of the Boston Marathon then killed three people - including an eight-year-old boy - and injured some 260 others.

U.S. District Court Justice George O'Toole began today by reminding jurors - the same ones who convicted Tsarnaev - that they swore an oath to deliver the appropriate punishment based solely on the law.

"The sole issue for your consideration is punishment," he said. "It is impossible to overstate the importance of the decision before you."

In the course of the trial, Tsarnaev's defense did not try to say Tsarnaev was innocent, but that his older brother Tamerlan, who was killed in a police shootout three days after the bombing, was the driving force in the deadly plot. Judy Clarke, Tsarnaev's lead attorney, began the trial by stating flatly, "It was him."

At the time, legal analysts told ABC News the strategy was not designed to win the trial, but to lay the groundwork for the penalty phase in hopes of sparing Tsarnaev's life.

Hundreds of runners completed this year's Boston Marathon Monday, including Rebekah Gregory, who lost her left leg in the 2013 blast. Gregory had taken the stand during the guilt-or-innocence phase of Tsarnaev's trial and later told ABC News she tried to meet her would-be killer's gaze.

"I could not look into his eyes because he wouldn't look at me," Gregory said. "But I tried to look him in the face several times and I wanted him to know I was not scared of him."

Though gratified with Tsarnaev's conviction earlier this month, prominent victims have since spoken out against giving Tsarnaev the death penalty in order to spare them potential years of appeals should he be so sentenced.

"The past two years have been the most trying of our lives. Our family has grieved, buried our young son, battled injuries, and endured numerous surgeries - all while trying to rebuild lives that will never be the same," Bill and Denise Richard, parents of Boston bombing victim eight-year-old Martin Richard, wrote in the Boston Globe Monday. "But now that the tireless and committed prosecution team has ensured that justice will be served, we urge the Department of Justice to bring the case to a close. We are in favor of and would support the Department of Justice in taking the death penalty off the table in exchange for the defendant spending the rest of his life in prison without any possibility of release and waiving all of his rights to appeal."

Tsarneav's family, for their part, said they believe Tsarnaev is the victim of a vast American conspiracy and maintain that he's innocent.