For the finale of their case as to why admitted Boston Marathon bomber Dzhokhar Tsarnaev should not get the death penalty, his defense team called Sister Helen Prejean, a famous opponent of capital punishment, to the stand on Monday.

The nun, portrayed by Susan Sarandon in 1995's "Dead Man Walking," told the courtroom that she believes Tsarnaev is "genuinely sorry for what he did," according to NBC News.

"No one deserves to suffer like they did," she said of the victims in the 2013 bombings.

Prejean, who runs a group called Ministry Against the Death Penalty, said she met with Tsarnaev five times while he has been in custody. Prejean said he "appeared remorseful" and "seemed sincere" while talking about the victims of the bombings, according to NBC News.

She explained to the jury that the organization she spearheads helps "people who have done terrible crimes" realize what they have done and come to terms with the consequences.

Tsarnaev did not show any emotion while Prejean testified and has not publicly expressed any throughout the trial. He did tear up and appear his most emotional when family members took the stand in his defense last week.

With the defense's case completed, the next step in the trial is closing arguments, which are expected to take place later this week. After that, the jury will being deliberating whether or not Tsarnaev should receive the death penalty or be sentenced to life in prison, most likely at supermax, without the chance of parole.