What's next for convicted Boston Marathon bomber Dzhokhar Tsarnaev

Dzhokhar Tsarnaev was found guilty on all 30 charges he faced for his role in the 2013 Boston Marathon bombings. His case now enters the penalty phase, where jurors must decide whether to impose the death penalty or life in prison.

Twelve jurors at the John Joseph Moakley U.S. Courthouse in Boston on Wednesday convicted 21-year-old Dzhokhar Tsarnaev on all of the 30 charges he faced for his role in the gruesome bombings at the Boston Marathon on April 15, 2013. The verdict comes as no surprise given the overwhelming evidence of Tsarnaev’s guilt. While Tsarnaev’s victims and their families might never gain closure from the pain and suffering inflicted by Tsarnaev, his guilty verdict nonetheless provides confirmation under the law that he waged terror against innocent persons.

Tsarnaev, along with his older brother, Tamerlan Tsarnaev, planned and detonated two pressure cooker bombs on Boylston Street in Boston while marathoners ran and spectators cheered. The detonations, which occurred about 13 seconds apart, killed three persons (Krystle Campbell, Lingzi Lu and 8-year-old Martin William Richard) and injured 264 others. Many of the injured sustained serious wounds, some of which required amputations of limbs. After surveillance video and other evidence identified the Tsarnaev brothers as the bombings’ culprits, a massive manhunt ensued around Boston. While on the run, the brothers killed Sean Collier, a campus police officer at the Massachusetts Institute of Technology. Tamerlan Tsarnaev would eventually be killed, with Dzhokhar's driving over him in a stolen SUV playing a major cause in his death. Police captured Dzhokhar Tsarnaev on April 19, 2013 while he was hiding in a boat parked in the backyard of a resident of Watertown, Mass., a suburb of Boston.

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​Tsarnaev’s trial began on March 4. For 15 days, jurors digested a compelling case-in-chief brought by the prosecution. Jurors heard testimony by those whom Tsarnaev maimed and by other victims’ family members. They also watched video of Tsarnaev planting a backpack containing bombs and ominously scanning the crowd of persons he sought to kill. Tsarnaev’s attorney, Judy Clarke, tried to defend Tsarnaev by asserting that his older brother had become self-radicalized and duped or coerced Dzhokhar into following his lead. As evidenced by the fact that jurors unanimously voted to convict Tsarnaev on 30 of 30 counts, this defense theory clearly did not work.

Although Massachusetts does not permit the death penalty in state homicide cases (an important point in the trial of Aaron Hernandez for the murder of Odin Lloyd), the Tsarnaev trial involves 17 federal charges that carry the possibility of the death penalty. Those charges include conspiracy to use a weapon of mass destruction, resulting in death, and conspiracy to bomb a place of public use, resulting in death. With convictions on these 17 charges in mind, jurors will now decide whether to sentence Tsarnaev to prison for the rest of his life or impose the death penalty. They could reconvene as soon as next Monday in U.S. District Judge George O’Toole’s courtroom to begin their decision-making process.

How Tsarnaev’s death penalty phase will work

The penalty phase could last weeks and will in some ways resemble the trial. As in the trial, the prosecution and defense will each offer opening statements. The prosecution will highlight “aggravating circumstances” under federal law that would warrant imposition of the death penalty. In contrast, the defense will stress “mitigating circumstances” under federal law that would warrant life in prison. Evidence and witness testimony will then be presented to jurors.

Witnesses for the prosecution will include victims and family members of victims. They will testify about how their lives have been irreparably harmed by Tsarnaev’s crimes. It is unclear who might testify on behalf of Tsarnaev, though any family members willing to speak for him would be helpful to his chances. Tsarnaev could also testify on his behalf if he so chooses.

Watch for the prosecution to emphasize the following aggravating circumstances:

​1. Tsarnaev carried out his crimes in an especially heinous, cruel and morally depraved manner. Tsarnaev’s plan to murder and maim innocent people, including children and older persons, through an act of terror seems clearly heinous. He caused one of the worst acts of terrorism in U.S. history and he irreparably harmed the lives of hundreds of persons and their family members. He also selected a public setting to cause widespread fear.

2. Tsarnaev engaged in substantial planning and premeditation. Prosecutors will highlight the time and energy Tsarnaev put into building pressure cooker bombs and mapping in advance where they would be placed to inflict the maximum harm on innocent persons.

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​3. Tsarnaev targeted especially vulnerable victims, including children. As shown on surveillance video, Tsarnaev looked at persons who he knew would be standing in range of the explosion. It stands to reason he either knew children and other vulnerable persons would be harmed or should have known.

4. Tsarnaev created a grave risk of death to additional persons. Not only did Tsarnaev cause harm to hundreds of victims, but he also placed many others in grave danger. This was particularly true when he attempted to flee and waged firefights and car chases with police officers on public streets and in neighborhoods.

Watch for the defense to emphasize the following mitigating circumstances:

1. Tsarnaev had limited capacity due to his brother’s influence. As in the trial, the defense will portray Tsarnaev as lacking complete decision-making capacity due to the corrupting influence of his older brother. This argument didn’t seem to work in the trial but might resonate more with jurors when it comes to deciding whether to impose the death penalty.

2. Tsarnaev was under duress due to fear of his brother. The defense might similarly contend that Tsarnaev had no choice but to participate in some aspects of the bombings because of fear of his brother.

3. Tsarnaev was a teenager when he committed the acts. Tsarnaev was 19 years old at the time of the bombing. While he was old enough to vote and attend the University of Massachusetts—and, the prosecution would stress, clearly old enough to build weapons of mass destruction—Tsarnaev was still relatively young and not fully matured. Jurors might hesitate to impose the death penalty on a young person.

4. Tsarnaev has no criminal record. A well-recognized mitigating circumstance in a federal death penalty case is that the defendant has no criminal record and is thus not a “repeat offender.” Tsarnaev has no criminal record.

Life in prison more likely than the death penalty

While a clearly compelling case can be made that Tsarnaev deserves the death penalty in accordance with federal death penalty factors, all 12 jurors must unanimously agree to impose it. On one hand, these 12 jurors have already signaled to the court that they are not philosophically opposed to the death penalty, as otherwise they would not have been selected as jurors. On the other hand, these 12 jurors are from Massachusetts, where the death penalty is generally unpopular. The Massachusetts Supreme Judicial Court, in fact, abolished capital punishment in 1984 (a decision that has no impact on federal cases). Given Tsarnaev’s age and lack of criminal record, it may be difficult for prosecutors to convince all 12 jurors to impose the death penalty on Tsarnaev.

It is also worth noting that juries in federal death penalty cases usually do not impose the death penalty. According to a 2014 study conducted by the Federal Death Penalty Resource Council, juries imposed the death penalty in 33 percent of cases where the defendant was convicted and could have been sentenced to death. In the remaining 67 percent of cases the defendant was sentenced to life in prison. Further, a person sentenced to death is not always ultimately executed. This person will have several opportunities to appeal and might also be granted clemency.

Lastly, there might be concern among jurors that sentencing Tsarnaev to death would turn him into a martyr for radical groups. Those groups could then use Tsarnaev to recruit young persons. If that were to happen, the goal of Tsarnaev’s sentencing would be severely undermined. 

Michael McCann is a Massachusetts attorney and the founding director of the Sports and Entertainment Law Institute at the University of New Hampshire School of Law. He is also the distinguished visiting Hall of Fame Professor of Law at Mississippi College School of Law.