07-07-2025
'Miscarriage of justice' fears over brother and sister's deaths in Pembrokeshire
New questions are being raised about the 1976 deaths of a brother and sister who were found dead in their farmhouse in Llangolman, Pembrokeshire.
At the time, Dyfed-Powys Police concluded that Martha Thomas - known as Patti - was killed by her brother, Griff, and that he died as a result of a fire he lit in the house.
In a special episode of Y Byd ar Bedwar on S4C, two experts in historical cases claim there is room for suspicion that someone else could be responsible for their deaths, raising the question that Griff Thomas may have been wrongly blamed for killing his sister.
For decades, relatives and those who knew them well have also insisted that Griff could not have killed his sister and that someone else was responsible.
Griff and Patti Thomas, aged 73 and 70, were living at Ffynnon Samson farm in Llangolman. Both were unmarried and had lived together throughout their lives.
However, on December 11, 1976, a murder investigation was launched after their bodies were discovered in their home. Two months later, the inquiry concluded that Patti had been unlawfully killed after suffering an assault at the hands of her brother.
An open verdict was reached regarding the death of Griff Thomas, but police believed he died after setting himself on fire.
Professor Niamh Nic Daed, head of the forensic department at the University of Dundee and one of the expert witnesses in the Grenfell Tower Fire Inquiry, said she has never encountered a similar case before.
"There were no ignitable liquids or liquid accelerants like petrol or paraffin or whatever used," she said.
"So the most likely cause of the fire was somebody deliberately setting fire to the combustible materials that were present. You then need to think about using your experience to determine whether that type of fire would be likely to be self-inflicted."
After reading the Dyfed-Powys Police report from 1976 on the investigation into the Thomas family's deaths, Professor Nic Daeid believes important questions arise, saying: "It certainly suggests to me that there are questions with regard to whether the fire was deliberately set by Griff, or whether it was the action of another person."
Stephanie Davies, a former senior coroner's officer who is now an independent investigator specialising in interpreting death locations, has also looked into the case.
While she states that the police investigation at the time was thorough, she feels there are important questions which remain unanswered.
"I think they fell at the final hurdle," she said. "There are quite a few red flags for third-party involvement.
"There needs to be a fresh inquest. When somebody has died they can't defend themselves, yet they can still be labelled a murderer on the balance of probabilities.
"That, I don't think is right. I think it is very possible it is a miscarriage of justice and I think it is only right for at least an inquest to explore those factors."
The programme also hears from relatives of Griff and Patti Thomas, who have been fighting for decades to clear their brother's name.
"My father, from the beginning, said that the story wasn't right," says Huw.
'It was just the two of them. Neither would ever have harmed the other, never.
'I was 15 at the time and I'm 63 now, who's going to fight on after my day? I feel deeply about the injustice of the whole thing.'
In October 2022, Dyfed-Powys Police announced it was conducting a forensic review of material which had been kept from the original investigation in 1976.
Two and a half years after the review was established, family members say they are still waiting to hear about any developments.
"I feel very strongly about this," said Huw. "How much longer is needed?"
Dyfed-Powys Police was asked for an interview for the programme. In a response, a spokesperson said: "The review is ongoing and we are not in a position to provide guidance on timelines. We will not be providing an interview at this time."
