Texas will witness the execution of 50-year-old Ivan Cantu on Wednesday for the homicide of his cousin and his cousin's fiancee in 2000 - a double murder he is adamant that he did not commit.

Cantu is one of two inmates to be put to death by lethal injection today in the US.

The other, convicted serial killer Thomas Creech, 73, who has been on Death Row for nearly 50 years for killing another inmate, will be executed in Idaho.

Cantu was convicted in 2001 for shooting dead his cousin, James Mosqueda, and Amy Kitchen, Mosqueda's fiancee.

Cantu's fiancee at the time, Amy Boettcher, testified at his trial that he admitted to committing the crime by taking her to Mosqueda's home to show her the bodies and look for hidden drugs. Evidence entered at the trial was a pair of jeans with the victims' blood found in Cantu's kitchen trash can.

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The defendant's lawyers maintain that Boettcher lied on the witness stand while the jeans, which were too large for Cantu, were planted by someone else. Boettcher has died since then.

The defendant insists that they were killed by a drug dealer to whom Mosqueda owed money.

'Serious uncertainties'

Those expressing doubts about Cantu's conviction were the Texas Catholic Conference of Bishops, which called for the halt of the execution over "serious uncertainties" in the case, and the foreman of the jury who presided over his 2001 trial.

In an article for Austin American-Statesman, Jeff Calhoun called for a delay in the execution for further investigation.

Kim Kardashian, who's active in prison reform, urged the state's conviction integrity unit to investigate further. "The time to act to save Ivan Cantu is now!" she wrote on X. 

Texas Gov Greg Abbott is last resort for 30 day reprieve for Ivan CANTU, set to die Wednesday, Feb 28. Urge him to use his power to allow time for new evidence in Ivan’s case to be evaluated, lest Texas execute a wrongfully convicted man. Urge the Gov to grant a 30 day reprieve…

— Kim Kardashian (@KimKardashian) February 27, 2024

Actor Martin Sheen, openly opposed to the death penalty, urged people on Instagram to sign the MoveOn petition, which calls for Texas Governor Greg Abbott to grant a stay of execution to Cantu, and it has already garnered nearly 150,000 signatures.

"Ivan was wrongfully convicted of murder more than 20 years ago," Sheen said. "Time is running out."

In an attempt to delay as well, a series of last-minute appeals have been filed by his lawyers.

Capital punishment has been abolished in 23 states, and governors of Arizona, California, Ohio, Oregon, Pennsylvania, and Tennessee have all put a hold on its application. 

This year, only one execution was recorded for an Alabama inmate who was the first to be put to death by nitrogen gas.

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Last year, 24 executions in the United States in 2023 were recorded, and all of them were done by lethal injection.

A recent Gallup poll shows that 53% of Americans - the lowest level since 1972 - are in favor of the death penalty for someone convicted of murder.