Texas to execute man convicted of stabbing wife, stepsons to death in 2007

By Brendan O'Brien

Sept 25 (Reuters) - A 45-year-old man convicted of stabbing his wife and two stepsons to death and sexually assaulting his two stepdaughters in their home in 2007 saying he believed his spouse was poisoning him is scheduled to be executed in Texas on Wednesday.

Robert Sparks is set to die by lethal injection at 6 p.m. (2300 GMT) at the state's death chamber in Huntsville.

A Dallas jury convicted Sparks of capital murder in 2008 in the deaths of his wife Chare Agnew and his two stepsons Harold, 9, and Raekwon, 10.

Sparks was accused of stabbing Agnew 18 times while she slept in their Dallas home on Sept. 15, 2017 before waking the boys up, bringing them into the kitchen and stabbing them to death.

Sparks proceeded to wake up his two stepdaughters LaKenya Agnew, 14, and Garysha Brown, 12. He tied them up and sexually assaulted them. He then told the girls that their mother tried to poison him, according to court documents.

Sparks locked his stepdaughters in a closet and left the home, stopping at his mother's house to borrow her car, and then his ex-girlfriend's home, where he told her he had killed his wife and two stepsons. He then called police and confessed, court records showed.

After traveling to Austin for a few days, Sparks returned to Dallas and was arrested. He told police his wife had been poisoning him. He provided blood, hair and fingernail samples, as well as a cheek swab, to be tested for evidence of poisoning, but investigators were unable to find a lab capable of that type of test, according to court papers.

As of Wednesday, Sparks has a pending request with the U.S. Supreme Court to stay his execution so his case can be reviewed. He argues that an expert for the prosecutor gave false testimony and a courtroom bailiff may have tainted the jury's death penalty decision by wearing a homemade tie depicting a syringe to show his support for the death penalty.

Sparks would be the 16th inmate in the United States and the seventh in Texas to be executed in 2019, according to the Death Penalty Information Center.

Texas has executed more prisoners than any other state since the Supreme Court reinstated the death penalty in 1976. (Reporting by Brendan O'Brien in Chicago; Editing by Bernadette Baum)