The baffling case of Robert Roberson, Texas death row inmate that made an 11th hour plea for mercy before his execution

A Texas man who has been on death row for over two decades for killing his two-year-old daughter is battling with the courts to overturn his conviction - claiming a debunked medical hypothesis and his undiagnosed autism put him behind bars. 

Robert Roberson III, 57, was sentenced to death for the killing of his daughter, Nikki Curtis at his home in Palestine, East Texas, in 2003. 

Roberson had taken her to hospital on January 31, 2002, and told staff there she had fallen from her bed after a period of being unwell. 

Nikki had serious head injuries, bruises on her chin, cheek and jaw, and a subdural hematoma, with one nurse later recalling how she was 'limp and blue'. 

Suspicious hospital staff called police after taking note of Roberson's seeming lack of emotion, and because of the nature of her injuries. 

Two decades on, a change in scientific opinion has brought about appeals from his legal team and caused a head detective who testified in the case to change his own mind on the guilty verdict. 

Robert Roberson III was sentenced to death for the February 2002 death of his daughter, Nikki Curtis

Prosecutors - and the jury - at the time determined she had died not from a fall but from being shaken to death by her father. Roberson was told he'd be executed. 

But in the years since, doctors have stepped away from assigning shaken baby syndrome (SBS) as a cause of death. 

The scientist who proposed it himself even admitted that it was being used to 'put innocent people in prison', warning in 2012 'we have gone badly off the rails'. 

The demeanor that made Roberson seem remorseless to police has also been thrust into a new light after his lawyers revealed he was diagnosed with autism while in prison. 

Hospital staff at the time had been suspicious of his seemingly flat affect and interpreted his response to his daughter's state as lacking emotion. 

They had also viewed his inability to explain her condition as a sign that he must have been lying to them. 

Roberson was given custody of Nikki by her maternal grandparents after her mother, who has remained unnamed was denied custody in the hospital after her birth.

In the week prior her death, Nikki had been sick and appeared at a local emergency room where she was prescribed Phenergan and sent home. 

After her condition didn't improve, doctors again prescribed her more Phenergan and codeine, an opioid now restricted from children under the age of 18.  

Phenergan now comes with a warning against being prescribed to children of Nikki's age.

The following night she had gone to sleep beside her father, who woke up to find her unconscious.  

Brian Wharton, a retired detective formerly with the police department in Palestine, was involved in the case in 2002.

Wharton was called to Palestine hospital after receiving reports of a mortally ill child being brought into the facility.

Hours after Nikki died, Wharton arrested Roberson even before an autopsy had been performed.

Roberson, seen here with his daughter Nikki, was prosecuted on what is now a widely discredited understanding of Shaken Baby Syndrome

The former detective said he spoke to a pediatrician and medical examiner and decided to follow their lead in what he described as seeming 'inexplicable'. 

Roberson was a parolee at the time of his daughter's death with previous convictions for burglary and theft and parole violations.

During Roberson's trial, Wharton would go on to testify against him - but his view of the guilty verdict has changed over the years.

In an op-ed published by the Dallas Morning News just last week, Wharton wrote that the state must halt his case before they make 'a tragic, irreversible mistake'.

Wharton said: 'I have thought that something went very wrong in Roberson's case and feared that justice was not served.

'If there is no movement to correct this injustice, I fear myself and others will carry our guilt eternally.

'I have come to believe that Nikki died of accidental and natural causes. I am convinced that she was not murdered. Roberson is innocent.

'There was no crime. I believe this because the 'science' that was used to obtain Roberson's arrest and conviction has changed drastically since his arrest.'

Roberson said that he found no sign of violence in the home where Nikki had collapsed and didn't look like she had been beaten.

THE EVIDENCE AGAINST HIM 

Multiple women testified that they'd seen Roberson shake and 'spank' Nikki when she cried. 

Among them were his girlfriend at the time, her daughter, and her niece. All of them claimed they had seen Roberson lash out at his daughter. 

Teddie Cox, his then girlfriend,  testified that Roberson had a bad temper and would frequently shake and spank Nikki when she wouldn't stop crying.

Cox's niece Courtney Berryhill also told the trial that when she spent the night at the home she witnessed Roberson shake Nikki by the arms to stop her crying. 

While Cox's daughter Rachel testified that she had witnessed him spank and shake Nikki, and also recalled a time he threatened to kill his daughter. 

Prosecutors initially said Roberson sexually assaulted Nikki, based on statements from a nurse, but dropped that element late in the trial when evidence could not conclusively support it. 

Doctors testified at his trial that Nikki's injuries were consistent with SBS and jurors found him guilty of capital murder

Prosecutors initially said Roberson sexually assaulted Nikki, based on statements from a hospital nurse, but dropped that element of the capital murder charge late in the trial 

At the time of his conviction in 2003, the consensus amongst the medical community was that Nikki must have been violently shaken and possibly struck

Nurse Kelly Gurganus told the trial that when Cox and Roberson appeared in the hospital, Nikki was already 'limp and blue'. 

She told the court that in her then five years of working as a nurse she had never seen anyone that shade of blue. 

Gurganus took the child to a trauma room and called for a doctor, while also observing bruising on Nikki's body.

When questioned by her, Roberson said the injuries were a result of falling off the bed.

It was Gurganus who instructed the director of nurses to call the police after not believing Roberson and when she spoke with him again testified that he appeared 'nervous and anxious'.

Pediatrician John Ross examined Nikki on the day she died and told the trial that her brain had shifted from the right side to the left. 

Ross said that in his opinion Nikki's injuries were not accidental but had been intentionally inflicted. 

Dr. Thomas Konjoyan treated Nikki the day she died, and testified that it would be 'basically impossible' for the injuries to have come from falling out of bed. 

UNDIAGNOSED AUTISM  

It wasn't until after he was imprisoned that Roberson was diagnosed with having autism spectrum disorder. 

His lawyers say that it was his autism that made him seem remorseless to police and hospital staff. 

Roberson had also been a special education student when he dropped out with an 8th grade education. 

The Innocence Project, who are backing Roberson, said that his autism was used against him. 

'SHAKEN BABY SYNDROME' DUBBED 'JUNK SCIENCE' 

Doctors who testified at his trial all said her injuries were consistent with SBS and jurors ultimately found him guilty of capital murder. 

At the time of his conviction in 2003, the consensus among the medical community was that Nikki must have been violently shaken and possibly struck. 

Medical opinion on SBS has now shifted dramatically in the last two decades, with evidence-based science widely disavowing it. 

Dr. Norman Guthkelch, who initially proposed SBS, said in 2012: 'I am frankly quite disturbed that what I intended as a friendly suggestion for avoiding injury to children has become an excuse for imprisoning innocent people. We went badly off the rails.' 

Roberson was a parolee at the time of his daughter's death with previous convictions for burglary and theft and parole violations

In April of this year, Roberson's attorney Gretchen Sween filed a motion asking for a hearing before any execution date is set for Roberson

Attorneys fighting for Roberson's release argue that new scientific evidence suggest it is impossible to shake a toddler to death without causing neck injuries. 

Nikki did not have serious neck injuries when she died in 2002, with attorneys also arguing that she had known breathing issues and head injuries.

In 2021, they also said that Nikki had undiagnosed pneumonia at the time of her passing, and had suffered from a violent illness days before her death. 

A Texas Court of Criminal Appeals stayed a 2016 execution and sent his case back to trial court to consider the 'junk science' claims. 

His appeals attorneys had argued that he did not have a fair trial due to his mental health expert not being allowed to testify to the brain injury claims. 

The second look at his execution was in part due to a new Texas statute that allowed trials to be revisited if flawed by false or misleading scientific evidence.

Texas became the first state in the country to pass the specific legal avenue into law, dubbed the 'junk science writ'. 

When the law was passed state lawmakers noted infant trauma as being one of the examples of science that the bill was intended to target. 

In January of last year, prosecutors said that evidence to convict Roberson was still 'convincing', arguing that SBS science had not changed as much as claimed. 

The year before, a local judge in Anderson County recommended that the Court of Criminal Appeals deny Roberson's request to overturn his conviction.

They said there was insufficient evidence to do so, with the high criminal court in the state also agreeing. 

In a last ditch attempt, attorneys last year filed a Supreme Court appeal that asked the court to review the case to deny a retrial despite the changing evidence. 

Attorneys fighting for his release argue that new scientific evidence suggest that is is impossible to shake a toddler to death without causing neck injuries

The petition asked the court to weigh whether a death sentence based on science presented to the jury as fact should be allowed when in the years since opinion has changed. 

The state lobbied the supreme court justices to persuade them not to take the case, citing testimony from Cox.

The Supreme Court ultimately denied the request with his last chance of being absolved now lying with Texas Governor Greg Abbott.

In April of this year, Roberson's attorney Gretchen Sween filed a motion asking for a hearing before any execution date is set for Roberson. 

The filing said that Roberson 'respectfully requests' his counsel to be part of a hearing before a court where both sides have an opportunity to be heard. 

It added that Roberson was praying for 'any further relief that justice warrants'. No execution date has been set for Roberson.

Speaking with The Guardian last year from inside the Allen B Polunsky Unit, Roberson said that Nikki had been sick from the day he got custody of her. 

After taking his daughter to the hospital following her alleged fall, he told the outlet that hospital staff immediately suspected him of hurting Nikki. 

He said that due to a troubled childhood, he had trained himself not to cry, adding: 'I got my behind whooped by my father who would say, "Shut up or dry it up or we’ll give you some more".'

'I would never think about shaking her. And that's the God's honest truth. I don't know what happened to her.

'I hope and pray that God gives them the knowledge for the people to make a righteous decision. I know I didn’t do it. I’m not guilty. So I’m at peace with the Lord.'

No date has yet been set for his execution.  

Since 1993 there have been 31 exonerations in the US following convictions for SBS, according to the National Registry of Exonerations. 

Roberson is currently housed inside the Allan B Polunsky Unit in Livingston, Texas, seen here

In September of last year, an appeals court in New Jersey ruled that the theory behind SBS was 'junk science' and 'scientifically unreliable'.

The court had been ruling in the case of Darryl Nieves who was arrested and charged after his son D.J. had a seizure in February of 2017.

Nieves had called 911 for his 11-month-old son, who was born 15 weeks premature, and suffered from several medical conditions having spent 7 months in hospital. 

Despite all of this, a child abuse pediatrician at the hospital diagnosed him as having abusive head trauma, or SBS. 

Nieves was charged with aggravated assault and child endangerment before being released four days later but was not allowed to contact his son. 

In January 2022, a trial judge sided with his defense and ruled that prosecutors couldn't produce testimony on SBS in his case. 

The appeals court ultimately sided with the judge who declared SBS to be 'junk science'.

Judge Greta Gooden Brown wrote that prosecutors must show a theory is accepted within the medical and scientific community. 

While in Ohio last year, Alan Butts was released after 19 years behind bars having been granted a new trial. 

Butts, like Roberson, was accused of SBS in the death of his girlfriend's 2-year-old son Jadyn in 2002. 

New evidence showed that Jadyn had pneumonia at the time of his death and was on medication no longer prescribed to children because it can cause sudden death.

The state attempted to appeal that new trial but was shot down by the Ohio Court of Appeals before his case was dismissed earlier this year.