HARRISBURG — Pennsylvania’s attorney general asked the state Supreme Court this week to nullify Gov. Tom Wolf’s moratorium on executing death row inmates, describing the policy as blatantly unconstitutional and a threat to the justice system.

Attorney General Kathleen Kane filed a request Monday in the case of Hubert Lester Michael Jr., on death row for killing 16-year-old Trista Eng in York County nearly 22 years ago.

“Never before has a member of the executive branch of government sought to unilaterally negate a criminal penalty across an entire class of cases,” Kane wrote. “Never before has a member of the executive branch affirmatively interfered with the proper administration of the law on the grounds that the judicial branch of government has not functioned in a way that meets a personal standard of satisfaction.”

The current situation puts at risk the integrity of the constitution, and the court should act to preserve it, the attorney general’s office wrote.

The filing was made quietly Monday and without fanfare, and Kane had not previously criticized Wolf’s stance in public. Wolf and Kane are both Democrats.

A Wolf spokesman said Wednesday that the governor is aware of the filing and plans to respond.

“It essentially makes the same arguments as the arguments currently pending before the court,” press secretary Jeff Sheridan said.

If the Supreme Court agrees with Kane, it could clear the way for the state’s first execution since 1999.

The attorney general’s office said Wolf’s three reprieves so far — “fall well outside the realm of his constitutional authority.”

Shortly after he took office, Wolf announced the new policy, saying the state’s system is “error-prone, expensive and anything but infallible.”

He has also issued a reprieve for convicted murderers Terrance Williams of Philadelphia and Robert Diamond of Bucks County. The high court is considering a challenge to Williams’ reprieve filed by the Philadelphia district attorney.