"I take this action only after significant consideration and reflection," Wolf said Friday. "There is perhaps no more weighty a responsibility assigned to the governor than his or her role as the final check in the capital punishment process."
Wolf, a Democrat who ran his family's cabinet manufacturing business before becoming governor in January, said the moratorium would be in place until a task force examining capital punishment in Pennsylvania issues its final report.
"If the Commonwealth of Pennsylvania is going to take the irrevocable step of executing a human being, its capital sentencing system must be infallible," he said. "Pennsylvania's system is riddled with flaws, making it error prone, expensive and anything but infallible."
It is a flawed system steeped in bigotry, according to Wolf.
"Numerous recent studies have called into question the accuracy and fundamental fairness of Pennsylvania's capital sentencing system," he said. "These studies suggest that inherent biases affect the makeup of death row. While data is incomplete, there are strong indications that a person is more likely to be charged with a capital offense and sentenced to death if he is poor or of a minority racial group, and particularly where the victim of the crime was Caucasian."
The governor stressed that the impetus was to re-examine a flawed system of justice, and in no way a sentence commutation for the 186 individuals on Pennsylvania's death row.
"This moratorium is in no way an expression of sympathy for the guilty on death row, all of whom have been convicted of committing heinous crimes," Wolf said. "This decision is based on a flawed system that has been proven to be an endless cycle of court proceedings as well as ineffective, unjust and expensive."
According to the Death Penalty Information Center, Pennsylvania has executed three inmates since the death penalty was reinstated in 1976, the last being in 1999. All were white males.
Wolf's action Friday has the most immediate effect on Terrance Williams, a convicted killer who was scheduled to die March 4.
A district attorney who is prosecuting a man charged with killing a state trooper decried Wolf's move as "unilateral and potentially unlawful."
Pike County District Attorney Raymond Tonkin's office last month said it would seek the death penalty in the case of Eric Frein, accused of killing Cpl. Bryon Dickson and injuring Trooper Alex T. Douglass in a September ambush outside a state police barracks in Blooming Grove, Pennsylvania.
Tonkin said Wolf's move "does not serve as any legal impediment to my office's pursuit of justice" in the case against Frein, charged with first-degree murder, terrorism and other counts.
"In announcing his action, the governor has usurped the authority of the legislature and courts in setting the lawful punishment for convicted killers. This unilateral action will only cause more pain and confusion to families who have suffered the actions of the worst criminals," Tonkin said.
Frein, who was arrested in October after a nearly seven-week manhunt, pleaded not guilty last month.