A Reform UK Member of the Senedd for Bridgend and the Vale has defected to Plaid Cymru, four months after she was elected under Nigel Farage’s banner.
Sarah Cooper-Lesadd, who represents Pen-y-bont Bro Morgannwg, announced on Tuesday that she had joined Plaid and its Senedd group, saying Reform “had no interest in the work I came here to do” and was “not serious about governing Wales”.
The move takes Reform’s group from 34 to 33. Plaid’s group chair, Marc Jones MS, said she becomes the party’s 44th MS, which leaves Plaid five short of a majority in the 96-seat Senedd.
It landed minutes after Dan Thomas resigned as Reform Wales leader, saying he had been reported to police at the weekend and released without charge.
“A real appetite in the group to want the government to fail”
Cooper-Lesadd, 31, had been Reform’s shadow minister for children, young people and skills since Thomas named his team in May, and chairs the Senedd’s Legislation Committee.
In a joint statement with Plaid, she said she had become increasingly uncomfortable with a party “far more interested in division, opposition and headlines than in finding solutions”.
“There is a real appetite in the group to want the government to fail,” she said, “and no interest in what that failure would mean for the people we represent.”
She said Reform members “oppose measures without any coherent explanation”, that she had wanted to vote for the Welsh Government’s supplementary budget, which she believed “every party should have supported”, and that she had argued against Reform tabling its debate on the Nation of Sanctuary policy.
Having sat that debate out, she said, she was criticised within the party. “Having just spoken about my own childhood trauma, I could not in good conscience sit through it.”
“I do not believe anyone should be scapegoated”
Cooper-Lesadd was born in Newport and spent her early childhood in the care system after her mother died three weeks after her birth. She was adopted out of Wales at seven, and told the Senedd her story in a debate on childhood trauma in July.
She said she could not support what she called Reform’s “attacks on people seeking sanctuary or other vulnerable groups”.
“I particularly reject the way minorities have too often been used as political targets. I do not believe anyone should be scapegoated or dehumanised to win votes, and I will not be part of a politics that does that.”
The Reform group in Cardiff Bay, she said, was “a staging post in the effort to get Nigel Farage into Downing Street”, something she said had been “glaringly obvious” at the party’s conference this week.
To those who voted Reform in May, she said: “I have not stopped listening to you. You told me you felt ignored and let down. Those concerns are real, and they will be answered by delivery, not division.”
The parachute, and the seat
Her route to the Senedd was not smooth. A former civil servant and Cambridge graduate, she stood for the Conservatives in Coventry East at the 2024 general election, coming second.
Reform’s Pen-y-bont list fell apart in the spring, as Swansea Bay News reported at the time: its original lead candidate quit over a photograph appearing to show him performing a Nazi salute, its second-placed candidate stepped back, and its sixth, Bridgend’s youngest councillor Owain Clatworthy, left the party accusing it of selecting candidates “with little or no connection to the communities they seek to represent”.
Cooper-Lesadd, who Nation.Cymru reported had originally been placed second on Reform’s list in Afan Ogwr Rhondda, was moved to the top of the Pen-y-bont list to replace him, and took the seat in May.
Plaid’s lead candidate against her, Mark Hooper, said at the time that Reform “cared nothing for Wales”. Hooper is now Deputy Minister for Transport.
Plaid: “not taken lightly”
Marc Jones said the group and Plaid’s national executive had agreed to admit her after “a period of reflection, discussion and a proper internal process”.
“A decision to allow a member to cross the floor, particularly from Reform UK, is not taken lightly,” he said. It had been “clear for some time” that she was “sincerely motivated by a desire to make a positive difference”, and that she was uncomfortable with Reform’s “politics, rhetoric and values”.
He acknowledged that many Plaid members had spent May campaigning against Reform. “Building our movement means reaching out, having conversations and persuading people and allowing people to change their minds.”
Cooper-Lesadd said she knew what she was asking of those members. “I will work to earn their trust.”
“The wheels are rapidly coming off”
Welsh Liberal Democrat leader Jane Dodds MS said the defection and the resignation together showed “the wheels are rapidly coming off Reform in Wales and the entire country”.
“Just months after they claimed they were ready to govern, one of their own frontbenchers has delivered a damning verdict that Reform aren’t serious about governing Wales and are more interested in division and headlines than actually improving people’s lives,” she said. “Wales deserves better than the chaos and constant scandal engulfing Reform.”
A Welsh Labour spokesperson said there were “serious questions about the stability of Reform and the choices being made by people elected under its banner just four months ago”. It would not be appropriate to comment on Thomas’s circumstances “while a police investigation is ongoing”, the spokesperson said, “but what is clear is that Reform is now without the leader who took it into the Senedd election, while another of its MSs has chosen to abandon the party altogether. People across Wales are facing real challenges and deserve serious, stable political leadership focused on their priorities.”
Reform UK Wales had not responded to the defection by Tuesday evening.
Related stories from Swansea Bay News
SENEDD: Reform Wales leader Dan Thomas quits four months in, saying he was reported to police and released without charge
The resignation that came minutes before the defection.
BRIDGEND CHAOS: Three of Reform’s six Pen-y-bont Senedd candidates have quit
The spring selection collapse that put Cooper-Lesadd at the top of the list.
SWANSEA: Francesca O’Brien handed housing and planning brief as Reform UK names its first ever Senedd shadow cabinet
The 14-strong team she was part of, now down to 13.
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