This undated file photo shows Kimberly McCarthy.

Chicago -

A Texas judge on Tuesday granted a last-minute reprieve to death row inmate Kimberly McCarthy, who had been scheduled to become the first woman executed in the United States since 2010.

District Judge Larry Mitchell postponed her execution until April 3 after her lawyers asked for time to bring forward an appeal on grounds of racial discrimination.

McCarthy - who has been on death row for 14 years - had been due to be executed at 6.00pm (23.00 GMT) after the US Supreme Court rejected her previous appeal.

“The previous warrant of execution is hereby recalled,” Mitchell wrote in a two-page order issued five hours before she was set to die.

“We are very pleased that we will now have an opportunity to present evidence of discrimination in the selection of the jury that sentenced Kimberly McCarthy to death,” defence attorney Maurie Levin told AFP in an email.

“As recognised by the US Supreme Court (Miller-El v Dretke, 2005), these facts must be understood in the context of the troubling and long-standing history of racial discrimination in jury selection in Dallas County, including at the time of Ms. McCarthy's trial.”

McCarthy, 51, is black. Her victim, 70-year-old retired professor Dorothy Booth, was white.

Despite the fact that her home county is 22.5 percent black, only one non-white juror judged McCarthy and three non-white jurors “were unilaterally excluded by the state despite being fully qualified to serve,” her lawyers wrote.

They further argued that 42 percent of people sentenced to death in Dallas county were black while 70 percent of the 24 men exonerated with DNA evidence in the same county were African Americans.

“A remedy is not only warranted, but demanded,” her lawyers argued Monday in a letter urging Texas Governor Rick Perry to issue a 30-day reprieve.

McCarthy was set to be just the 13th woman executed since the death penalty was reinstated in the United States in 1976.

She was convicted of forcing her way into her elderly neighbour's home near Dallas under the pretext of borrowing some sugar in 1997, court records show.

She then smashed Booth in the face with a candle stick, stabbed her five times and cut off her finger to steal her diamond ring.

McCarthy drove off in Booth's Mercedes and tried to buy some crack, court documents showed. She also used Booth's credit cards at least four times and pawned her wedding ring for $200 before she was caught.

Prosecutors also accused her of killing two other elderly people.

She was sentenced to death in 1998, saw her conviction overturned on appeal and then was convicted and condemned again in a second trial in 2002.

“It is a shame that courts allowed Ms. McCarthy to come so close to execution before granting the stay,” said Richard Dieter, director of the Death Penalty Information Centre.

“There certainly are signs and a history of racial discrimination in jury selection in Dallas County.”

There is also a good chance that she would not be sentenced to death if tried now due to mitigating factors like her drug addiction, Dieter told AFP.

Texas was sentencing as many as 40 people to death a year before the courts began providing juries with the alternative sentence of life without parole. That number has now since dropped to about eight people a year, Dieter said.

McCarthy would have been the fourth woman executed in Texas since 1976, out of a total of 493. Nine other women are among the 304 people on the state's death row.

A dozen women were among the 1 321 people executed since 1976, according to the Death Penalty Information Centre. Of the 3 199 people on death row as of October 1, 63 were women and 42 percent were black. - Sapa-AFP