ARTHUR EXECUTION DATE: Judge refuses to withdraw death warrant for Arthur Brown Jr, convicted of killing 4 at home in Houston

Here’s everything you need to know about the case:

Who is Arthur Brown?

Brown has been on death row in Texas since 1994. He was 21 years old at the time of the murders of four people in southwest Houston and lived in Alabama.

He maintains his innocence in the crime, and his lawyers say he was wrongly convicted because of withheld evidence and faulty eyewitness testimony.

In addition, Brown is believed to have an intellectual disability that his attorney investigated — he achieved a low IQ score as a child and was placed in special education classes, according to records. Brown had a rough childhood with an alcoholic mother and abusive father, which may have contributed to his disability.

If his lawyers were to prove his intellectual disability, he could be ineligible for the death penalty. A US Supreme Court decision in 2002 made it illegal to execute defendants with an intellectual disability.

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His circumstances have led people to show support with a petition to pardon him, including a push from billionaire Richard Branson.

Who is Arthur Brown accused of killing?

On the night of June 20, 1992, police say Brown robbed the drug house of Rachel Tovar in southwest Houston. He and two accomplices, Marion Dudley and Anthony “Antonio” Dunson, tied six people with sheets and shot them execution style in different rooms. The victims were Rachel and her husband Jose Tovar, their son Frank Farias, their pregnant daughter-in-law Jessica Quinones, their neighbor Audrey Brown and acquaintance Nicholas Cortez. Rachel Tovar and Cortez were the only survivors.

Brown fled Texas and was caught months later in Alabama. While police have linked the shooting to drugs, only small amounts of marijuana were found.

Dudley was killed by authorities in 2006, while Dunson is serving a life sentence in Huntsville – he is eligible for parole in 2027.

BROWN SAMPLE: Texas inmates want to halt execution, say Harris County prosecutors withheld evidence in 1993 trial

What evidence is there that Arthur Brown killed the victims?

There is more evidence that remains inconsistent all these years later.

After the shooting, when the two surviving victims were in the hospital, the police questioned them both. Tovar identified her assailants through photos investigators showed her, including Brown. But defense attorneys believe Tovar’s medical records point to brain damage that may have affected her “ability to serve as an accurate or reliable eyewitness” during the investigation and trial.

Tovar’s medical records, along with other evidence, were withheld from Brown’s defense at the time of the trial.

At Brown’s trial, Cortez identified Brown as the shooter but was unable to pick him out from an array of photos at the hospital.

A transcript of a police interview with Tovar’s son suggested another man was guilty of the murders, but that was withheld from the defense at trial.

Another shaky piece of evidence came from Brown’s sister, Carolyn Momoh, who told police that Brown confessed to the murders. But she later said the police forced her to make the statement.

Finally, during the trial, a firearms expert argued that the bullets used to kill the victims came from two guns associated with Brown and his accomplices. But in 2015, two independent weapons experts found there was no way to conclude the bullets came from the particular weapons used.

What is the status of the execution of Arthur Brown?