By Charlotte Huffman

PHILADELPHIA (CBS) — Life or death for Dzhokhar Tsarnaev?

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That decision is now in the hands of the same 12 jurors who on Wednesday convicted the Boston Marathon bomber on all 30 counts.

The penalty phase is expected to begin next week.

During the phase which could last anywhere from a few days to a few weeks, new witnesses will likely be called to testify and new evidence will likely be introduced.

The jury’s job will be to weigh aggravating versus mitigating factors to determine if Tsarnaev deserves to die for the bombing that killed three and injured more than 250 people.

Tsarnaev faces life in prison or execution.

During opening statements in the trial, the defense admitted “he did it.”

Philadelphia criminal defense attorney Bill Brennan says that admission was a tactical move by a defense team that has appeared to be focusing on the penalty phase from the start.

“The defense seems to have not challenged Tsarnaev’s guilt in the hopes that they would get to this stage with a client who is not unanimously hated by this jury. And if (the defense) was successful, then the mitigating factors will be; his youth, the fact that he was impressionable and the fact that it was his own older brother – an authority figure in his life – that ‘brainwashed’ him if you will into committing these acts,” said Brennan of Brennan Law Offices.

But Brennan says even that argument is “going to be a tough sell after 30 convictions and an act of terrorism.”

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Defense attorney, Judy Clarke will have to go back to the same 12 jurors that just convicted Tsarnaev on all 30 counts – and try to convince them not to execute him.

Brennan expects Clarke to try to show the jury how consecutive life sentences will assure that Tsarnaev will never see the light of day again.

For the prosecution, a much easier road is ahead.

“The prosecution will argue that this kind of case is the textbook example of why we have capital punishment and if not in this case, then when?” said Brennan.

In order to put Tsarnaev to death, the jury must side with the prosecution on at least one count that carries capital punishment.

A unanimous decision is required.

Considering the jury convicted Tsarnaev on all 30 counts, 17 of which carry capital punishment, the prosecution has 17 different chances to get a unanimous decision that puts Tsarnaev to death.

“It would be a huge defense result if this man is not put to death … This is an American case, the United States of America versus Mr. Tsarnaev and he’s just been convicted of committing an act of terrorism against our country. I think these jurors will go in there as Americans,” said Brennan.

On the contrary, if the mitigating factors presented by the defense are compelling enough to get just one juror to break from the pack and side with the defense on all 17 counts, that single juror would in effect stop Tsarnaev from execution.


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