Daniel Thomas has resigned as Reform Wales leader after being arrested on suspicion of assault. Reform is now entering a process to choose his replacement.
Sarah Cooper-Lesadd switched to Plaid Cymru on the same day, adding another change to a party already dealing with defections and leadership turnover. Reform supporters also accused her of betrayal and disrespect for her mandate.
Reform Wales and Sarah Cooper-Lesadd
The same day brought another move in Wales politics. Sarah Cooper-Lesadd defected to Plaid Cymru, while Dan De’Ath posted on X about her move and used the line: "No, I’m sure this can’t be true. She must’ve just undergone a complete ideological rebirth, abandoning her entire political outlook, values and worldview in three short months – going from the hard right to a steadfast champion of the world’s huddled masses. As people often do."
Reform MSs and supporters accused her of betrayal and disrespect for her mandate. That reaction sat alongside the resignation of Thomas, which leaves Reform Wales with a vacancy it now has to fill.
Westminster MPs and Reform
The party’s internal strain is not limited to Wales. Reform has four MPs in Westminster who defected after the last election, a point that has already shaped criticism around loyalty and mandate inside the party.
Danny Kruger posted on X that "The pirate ship analogy is now well out of date. Over the last year Reform has professionalised, organised, and is now rolling out a state-of-the-art plan for the election campaign whenever it comes." His message presented a party trying to project order while its Welsh leadership changes again.
Llŷr Powell had earlier been described as the presumptive Reform Senedd supremo before Thomas arrived. That makes the leadership handover more than a routine personnel shift: Reform in Wales now has to decide whether to lean on the same figures again or widen the search.
Caerphilly bye-election count
The party’s recent public setbacks in Wales have also fed the sense of churn. At the Caerphilly bye-election count, Zia Yusuf fled the scene in a car, another moment that drew attention to how Reform has been handling high-pressure events in the country.
With Thomas gone, the immediate task is organisational rather than rhetorical. Reform has to run its process, settle on a new leader, and do it while scrutiny over defections, loyalty and party discipline is still active.
The unanswered point is the one Thomas himself left open: what specific events led to his arrest and resignation. Until that is addressed, Reform Wales is left managing the vacancy rather than the explanation.
