HARRISBURG, Pa. (AP) — Newly elected Gov. Tom Wolf imposed a moratorium on the death penalty in the state Friday, calling the current system of capital punishment “error prone, expensive and anything but infallible.”

The Democrat said the moratorium will remain in effect at least until he receives a report from a legislative commission that has been studying the topic for about four years.

“If we are to continue to administer the death penalty, we must take further steps to ensure that defendants have appropriate counsel at every stage of their prosecution, that the sentence is applied fairly and proportionally, and that we eliminate the risk of executing an innocent,” Wolf said in a memorandum announcing the policy less than a month into his first term in office.

The Pennsylvania District Attorneys Association said Wolf had no authority to impose the moratorium, calling it a misuse of the concept of a reprieve.

“He has rejected the decisions of juries that wrestled with the facts and the law before unanimously imposing the death penalty, disregarded a long line of decisions made by Pennsylvania and federal judges, ignored the will of the Legislature, and ultimately turned his back on the silenced victims of cold-blooded killers,” the association said in a written statement. (See Full Statement)

An association spokeswoman said legal action in response was likely, and possible options were already being discussed at a meeting Friday of the group’s executive committee in Pittsburgh.

The head of the Pennsylvania State Troopers Association called the decision a sad day for the state and noted that Eric Frein, accused of killing state trooper Cpl. Bryon Dickson in the Poconos last year, would have faced a potential death sentence if convicted.

“Gov. Wolf’s decision today is a travesty because it prevents the commonwealth and the family of Cpl. Dickson from securing the penalty that is deserved. This decision also will affect the families of victims from all across the state who have had their loved ones torn from them due to senseless acts of violence from dangerous criminals,” said the group’s president, Joseph Kovel.

Wolf said data suggests that defendants might be more likely to be charged with capital murder and sentenced to death if they are poor or a racial minority and the victim is white.

“If the commonwealth of Pennsylvania is going to take the irrevocable step of executing a human being, its capital sentencing system must be infallible,” Wolf wrote. “Pennsylvania’s system is riddled with flaws, making it error prone, expensive and anything but infallible.”

Wolf said he is granting a temporary reprieve to Terrence Williams, scheduled for execution March 4 for killing two men. He has admitted killing them while in his teens but now says both men had been sexually abusing him.

Pennsylvania’s death row, which has been shrinking, houses 183 men and three women, but the state has executed only three people since the U.S. Supreme Court restored the death penalty in 1976. All three had voluntarily given up their appeals.

The most recent execution was Gary Heidnik in 1999, convicted of killing two women he had imprisoned in his Philadelphia home.

The reasons for the state’s lack of executions have long been debated in Pennsylvania legal circles. Some have attributed it to death penalty opposition among judges on the 3rd U.S. Circuit Court of Appeals or to aggressive tactics by lawyers who defend people facing execution.

Others say the number of stayed or overturned death sentences demonstrates there are flaws in how those cases are handled, particularly when it comes to providing adequate representation at trial.

Wolf had promised a death penalty moratorium during his fall campaign against his predecessor, Republican Gov. Tom Corbett.

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