The Arizona Republic regional newspaper reported on Monday that the US state declared its intention to retry Debra Milke on the same day that she was due to be released. She has been on death row for the past 20 years.

Milke, the daughter of a German mother and American father, was convicted by a court in Arizona in 1990 for plotting to have her four-year-old son killed.

But it emerged that the sole evidence against her – the claim by ex-police officer Armando Saldate that Milke had confessed to the crime – was unreliable because Saldate had an extensive history of lying under oath.

In 1989, Milke’s son was taken on an outing by a man who was living with them at the time on the understanding, she claimed, that he was going to see Santa Claus in a shopping centre. Instead, the man and an accomplice drove the child to the desert, where he was shot dead.

Both men, who blamed each other for the crime, were sentenced to death and are approaching the end of their appeals.

Milke has always maintained her innocence. The Arizona court that convicted her in 1990 had relied solely on the testimony of the police officer. No written or recorded evidence of the supposed confession has ever been produced and it has since emerged that the individual in question had a track record of lying under oath, as well as a history of other misconduct.

According to the March ruling of judge Alex Kozinski of the San Francisco Court of Appeals, Milke did not receive a fair trial and there was no evidence to suggest she had any involvement in the death of her son.

Kozinksi criticized prosecutors for remaining “unconstitutionally silent” about the officer’s history of deceit.

In March, Arizona Attorney General Tom Horne said he would personally argue on the state’s behalf if the case went to the US Supreme Court. In a written statement, he said that Milke had been found guilty of a “horrible crime” and that the Court of Appeals’ decision “needs to be reversed.”

Neither Milke’s defense team nor the jury in Arizona had been aware that previous judges had discarded four confessions made by Saldate because of his history of lying.

Despite his history of deceit, Saldate is expected to give evidence at the re-trial, The Arizona Republic reported.

The Local/kkf