Prosecution to Appeal Arizona Death Row Inmate Debra Milke's Overturned Murder Conviction

March 15, 2013 — -- After a three-judge panel threw out the conviction of an Arizona mother who spent 22 years on death row for the killing of her 4-year-old son, Arizona Attorney General Tom Horne said he plans to appeal the decision to the U.S. Supreme Court.

"If the court takes the appeal, I will argue it personally, as I have done in two previous cases over the past five months," he said in a prepared statement.

"After dressing him up and telling him he was going to the mall to see Santa Claus, [Debra Jean] Milke was convicted of sending her young son off to be shot, execution style, in a desert wash. This is a horrible crime. The Ninth Circuit's decision needs to be reversed, and justice for Christopher needs to be served," Horne said in the statement.

A panel of the 9th U.S. Circuit Court of Appeals ruled Thursday that Milke's murder conviction would not stand after the panel determined it was based on the testimony of a detective who had an undisclosed history of misconduct.

"Milke's conviction was based largely on the testimony of police Det. [Armando] Saldate [Jr.], who allegedly obtained her confession," the court wrote in its decision. "The panel held that the state remained unconstitutionally silent instead of disclosing information about Det. Saldate's history of misconduct and accompanying court orders and disciplinary action."

According to the court ruling, Saldate Jr.'s previous transgressions included lying to internal affairs investigators, lying under oath and violating suspects' rights.

The court of appeals' ruling mandated that Arizona authorities must provide Milke's attorneys with the detective's personnel files, which previously were not disclosed. Once they do, the prosecution then has 30 days to decide whether or not they'll retry Milke.

If they do not retry Milke, "she would walk free," Milke's attorney Michael Kimerer told ABCNews.com.

Meanwhile, there may be sanctions for Saldate, as well as his superiors, Kimerer said.

Saldate did not immediately respond to ABC News' requests for comment.

Despite the ruling, Milke, 48, has not been removed from death row, as a result of Department of Corrections' policy, Kimerer said.

Milke is in a state of shock, he said.

"She's been sitting there every day for almost 20 months anticipating this opinion," he said of his client, who he has represented since 2000.

"You sit there almost 23 years on death row with the specter of death hanging over your head and suddenly it's gone, and she needs to adjust how to react to it all."

ABC News' Colleen Curry contributed to this report.