With three days remaining in a six-day span of executions, four men are watching the clock as they await their scheduled deaths. The series began on Friday with South Carolina’s execution of Freddie Owens, despite new doubts about his guilt.

Owens’ execution will be followed by two double executions on Tuesday and Thursday.

On Tuesday, Texas plans to execute Travis James Mullis for the 2008 murder of his infant son, while Missouri is set to execute Marcellus Williams for the 1998 fatal stabbing of a former reporter, despite prosecutors and the victim’s family urging clemency.

After Tuesday’s back-to-back executions, Thursday is expected to bring another double execution in Alabama and Oklahoma.

Alabama plans to use nitrogen gas to execute Alan Eugene Miller, convicted of the 1999 shooting deaths of three co-workers, despite evidence of his mental illness. A witness to the state’s previous nitrogen gas execution in January described the method as “horrific.”

Oklahoma is set to execute Emmanuel Littlejohn in the death of a convenience store clerk in 1992 despite his arguments that he wasn’t the shooter

The United States has long been criticized for its use of the death penalty, but several states still allow executions.

How many states have the death penalty?

According to the Death Penalty Information Center, 21 states still practice the death penalty:

• Alabama
• Arkansas
• Florida
• Georgia
• Idaho
• Indiana
• Kansas
• Kentucky
• Louisiana
• Mississippi
• Missouri
• Montana
• Nebraska
• Nevada
• North Carolina
• Oklahoma
• South Carolina
• South Dakota
• Texas
• Utah
• Wyoming

Six states still consider the death penalty legal but have put executions on hold for various reasons: Arizona, California, Oregon, Ohio, Pennsylvania and Tennessee.

Texas leads the nation in death penalty numbers

Texas has carried out 589 executions, more than four times the number of the second-leading state for the death penalty.

The following are the five states with the most executions since the early 1980s, according to the Death Penalty Information Center:

1. Texas: 589
2. Oklahoma: 125
3. Virginia: 113
4. Florida: 106
5. Missouri: 99

Last year, Texas executed eight inmates and has executed three so far this year, with at least three more scheduled by the end of 2024.

Texas man challenging ‘shaken baby syndrome’ conviction based on ‘junk science’

One of those scheduled is Robert Roberson, whose conviction for “shaken baby syndrome” has sparked significant controversy. Many believe he was wrongfully convicted based on “junk science” and that he is not responsible for the death of his 2-year-old daughter, Nikki.

Texas legislators and the Texas Coalition to Abolish the Death Penalty assert that Roberson is innocent, arguing he has spent over 20 years on death row for a “crime that never occurred.” They contend that “new scientific and medical evidence” suggests Nikki, who was chronically ill, died of natural or accidental causes, and that Roberson should not be held accountable.

Roberson maintains his innocence. In 2016, after Texas became the first state to pass a “junk science law”—which allows individuals to appeal convictions based on debunked forensic science—he filed a new writ of habeas corpus. In the motion, he claimed that new scientific evidence contradicted the shaken baby syndrome theory used to convict him, that the evidence used at trial was scientifically invalid, that he was innocent, and that the use of scientifically invalid evidence violated his right to a fair trial.

Since the law was enacted in 2013, no Texan on death row has successfully secured a new trial. Last week, the Texas House majority advocated for his clemency.

If the execution scheduled for Oct. 17 is carried out, Roberson would become the first person in the United States to be put to death based on a shaken baby syndrome diagnosis.

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