A federal judge in Indiana late on Monday blocked the execution of convicted murderer Lisa Montgomery, the only woman on federal death row in the United States, on mental health grounds, based on evidence that she was unable to understand the government's rationale for her execution.
Prosecutors have filed a notice to appeal the judge's ruling, CNN reported on Tuesday.
Separately, the US Court of Appeals for the District of Columbia circuit, also voted to stay the execution, pushing any new execution date into Joe Biden's administration unless the Supreme Court intervenes.
Montgomery, who was due to be killed by lethal injection on Jan. 12, was convicted in 2007 in Missouri for kidnapping and strangling Bobbie Jo Stinnett, then eight months pregnant. Montgomery then cut Stinnett's fetus from the womb. The child survived.
US judge James Patrick Hanlon granted a stay of execution to allow the court to conduct a hearing to determine whether Montgomery is competent to be executed on mental health grounds, according to a court filing made in the US district court of Southern District of Indiana.
Montgomery's lawyer, Kelley Henry, welcomed the judge's ruling and said the court was right to put a stop to her execution.
"Mrs Montgomery is mentally deteriorating and we are seeking an opportunity to prove her incompetence," Henry said in a statement.
Montgomery's lawyers have asked for US President Donald Trump's clemency, saying she committed her crime after a lifetime of being abused and raped. In a nearly 7,000-page clemency petition filed last week, they asked Trump to commute Montgomery's sentence to life in prison.
The lawyers have said Montgomery admits her guilt but deserves clemency because she has long suffered severe mental illness, exacerbated by being gang raped by her stepfather and his friends during an abusive childhood.
Federal executions had been on pause for 17 years before Trump ordered them to resume last year.
In 2020, the US government executed 10 people. It was the first time the federal government conducted more executions than all US states combined, according bit.ly/3nCBdB0 to a database compiled by the Death Penalty Information Center.