Life in prison would be a much worse punishment than the death penalty, defense attorneys for Boston Marathon bomber Dzhokhar Tsarnaev argued Monday during the penalty phase of the trial. While he has already been convicted for his role in the bombing, the jury now must decide whether to sentence Tsarnaev to life in a supermax prison or impose the death penalty.

"Maybe we could've shown you this and stopped," attorney David Bruck said, showing pictures of a supermax prison to jurors, according to NBC News. "He'd go here and be forgotten. His legal case would be over for good, and no martyrdom.”

It’s a new argument from Tsarnaev’s defense, which had been expected to focus their efforts on his older brother Tamerlan, 26, portrayed as key in influencing Dzhokhar -- also known as Jahar -- to participate in the bombing. “If Tamerlan hadn’t been in the picture, would Jahar have done this on his own?” Bruck asked the jurors, according to the New York Times.

The jury is the same one that convicted Tsarnaev, 21, of all 30 counts, which included but were not limited to: using weapons of mass destruction, bombing a place of public use, conspiracy and aiding and abetting, according to CNN. How they choose to punish him, however, isn’t expected to be as clear. Even in Massachusetts, the state where the bombings occurred, only 15 percent of residents say Tsarnaev should be executed, a Boston Globe poll indicated. And the defense’s latest argument mirrors one by Bill and Denise Richard, parents of Martin Richard, 8, who was killed in the bombings.

“You’ll punish him and protect society at the same time,” Bruck said, according to “As awful as this crime was, a lifetime in prison to face what he has done is the better choice. For everyone.”