PHOENIX (AP) -- The case against an Arizona mother whose 1990 conviction in her son's killing was overturned by an appeals court should be dismissed based on lack of evidence because the key witness against her refuses to testify at her retrial, defense attorneys wrote in a motion.
Debra Milke was found guilty of first-degree murder, among other charges. Authorities say she had two men shoot her 4-year-old son in the head in the desert outside Phoenix in 1989. But after more than two decades on death row, an appeals court overturned the conviction last year.
Milke has since been released on bond awaiting a 2015 retrial.
Prosecutors had no comment Wednesday on the defense motion filed this week and have yet to file a response.
In the motion, defense attorneys argue the case should be dismissed with prejudice, meaning prosecutors couldn't try her again, after the detective who told jurors Milke confessed has now asserted his Fifth Amendment right against self-incrimination and is refusing to testify again.
The case against Milke rested largely on the purported confession, which now-retired Phoenix police Detective Armando Saldate did not record, so jurors were left with his word alone that she told him of her involvement. Milke has maintained her innocence and denied she ever confessed. The two men convicted in the child's death did not testify against her and remain on death row.
Milke's attorneys argue that Saldate's refusal to testify has "effectively gutted" the state's case, given that without his testimony, the confession likely cannot be used at her retrial.
They note that "the only direct evidence linking defendant to the crimes is the defendant's alleged confession to Saldate."
"Ms. Milke, who has already served 23 years on death row and whose conviction was reversed nearly one year ago on the basis of `flimsy evidence' and the testimony of a seriously discredited (and now unavailable) detective, has the right to move forward with her life," defense lawyers wrote.
The 9th U.S. Circuit Court of Appeals ruling overturning her conviction cited, in part, the prosecution's failure to reveal evidence to defense attorneys that could have called into question Saldate's credibility. The panel also found that Milke had not waived her right to have an attorney present for his interrogation of her.
The appeals court cited numerous instances in which Saldate committed misconduct in previous cases, including lying under oath and violating suspects' rights, details that were not provided to Milke's defense lawyers during her trial.
Saldate has not returned repeated phone calls from The Associated Press seeking comment.
Judge Rosa Mroz has already denied a prosecution request to reconsider her ruling that allowed Saldate to assert his Fifth Amendment right. Prosecutors plan to appeal to a higher court.
Defense attorneys argue that even if Saldate testified, the appeals court ruling "casts serious doubts on the validity of the defendant's alleged confession."
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