Dylann Roof and death penalty: Does it matter what victims' families want?

If convicted of killing nine people during a Bible study at Emanuel AME Church in Charleston, S.C., Dylann Roof would almost surely face the death penalty.

Gov. Nikki Haley (R) has called for it. One of Mr. Roof's uncles has said that he would "push the button" himself if Roof is found guilty. Even Joseph Riley, the Democratic mayor of Charleston who opposes the death penalty, has said he has "no doubt" that the death penalty will be sought. "If you're going to have a death penalty, then certainly this case would merit it," he said.

A number of factors add perhaps a sliver of doubt. In South Carolina and beyond, mounting questions about the fiscal cost and practical application of the death penalty have cut death penalty convictions – though it's difficult to imagine those concerns influencing such a visceral case. 

Instead, perhaps most interesting in the Charleston case is the wishes of the victims' families themselves. Only two days after the shooting, relatives were telling Roof – via a live video link – that they forgave him.

In the past, such statements have been of limited value in court proceedings. As recently as the Boston Marathon bombing, a plea to drop the death penalty from the parents of the youngest victim killed went unheeded.

But as Roof faces mounting calls to be executed, it is possible that the greatest advocates for this life could be the loved ones of the very people he is charged with killing.

The case comes at a time when support for the death penalty nationwide is dropping. Though 56 percent of Americans support the death penalty, that's down 22 percent from 1996, according to the Pew Research Center.

The exoneration of convicts on death row has played a part in the dropping support, but other factors have been just as powerful – if not more so – in a drop in death penalty convictions pursued by prosecutors.

Like many states, South Carolina is having difficulty procuring the right drugs to carry out executions humanely. Attempts with other drugs appear to have caused intense pain for those being executed, with Ohio establishing a temporary moratorium. Nebraska went so far as to abolish the death penalty this year.

Nebraska was also concerned about the cost of putting someone on death row. Death-penalty cases involve a disproportionate number of appeals. According to a study by Seattle University, a death penalty case can add $1 million to the tab.

In South Carolina, these issues have led to a steady decline in death penalty convictions during the past decade, with no one sentenced to death since 2010.

For example, in 2012, one prosecutor at first planned to seek the death penalty for a mother who killed her two children, but he changed his mind. "Once you file for the death penalty, the clock gets moving and the money, the taxpayers start paying for that trial," he said, according to the Death Penalty Information Center, an anti-death penalty website.

The circumstances of the crime in Charleston last week could very well outweigh these concerns. "We will absolutely want him to have the death penalty,” Governor Haley told NBC's "Today" show.

But calls for the death penalty are raising the question of whether the wishes of the victims' families matter.

In Boston, they did not. The parents of 8-year-old Martin Richard, the youngest victim killed in the attack, made a plea in The Boston Globe that Dzhokhar Tsarnaev not receive the death penalty. They argued that a death penalty conviction – with all its appeals – would harm their ability to heal.

"We know that the government has its reasons for seeking the death penalty, but the continued pursuit of that punishment could bring years of appeals and prolong reliving the most painful day of our lives," they wrote. 

The jurors (who were already sequestered when the article was published) sentenced Mr. Tsarnaev to death.

But in Charleston, victims' families have already begun making very public statements of forgiveness. And while the Richards refused even to write Tsarnaev's name, the victims' families in Charleston addressed Roof directly, arguing for mercy – not for themselves, but for Roof.

"We already forgive him for what he’s done, and there’s nothing but love from our side of the family," teenager Chris Singleton, whose mother was killed, told BBC News.

It's unclear whether these statements reflect any bias against the death penalty. But the Rev. Clementa Pinckney, the state senator who was leading the Bible study at Emanuel AME Church in Charleston and was also killed, was working with the Death Penalty Resource & Information Center – an anti-death penalty group – to defeat a state law that would keep all information about executions secret.