Chris Evans, the Labour MP for Caerphilly, said: “Hefin’s passion and dedication for Caerphilly was evident in all he did, and I will greatly miss him as a colleague and friend.”
Plaid Cymru leader Rhun ap Iorwerth said: “I’m deeply shocked and saddened to learn of the passing of Hefin David.
“Hefin represented his constituency with tireless dedication. He brought passion, energy and independence of thought to Senedd proceedings. Our parliament will be poorer without him.”
Vaughan Gething, the ex-first minister who was supported by Dr David to run for leadership, said: “Hefin was funny and intelligent with a passion for social justice and his community.
“Much more importantly, he was my friend. It was a pleasure to sit next to him in the Senedd but also to share time together outside politics.
“He will be hugely missed by so many of us. My thoughts are with his family and Vikki.”
In 2023, Dr David published an important report, entitled Transitions to Employment, on empowering disabled people to overcome barriers to employment.
Luke Fletcher, Plaid Cymru’s shadow economy secretary, said: “Hefin made a significant contribution to education policy over the years and I always appreciated our conversations, particularly on apprenticeship policy.”
Laura Anne Jones, a Tory who defected to Reform UK last month, said: “Hefin was a genuinely lovely person. Regardless of political differences, we got on well. He always had time for a kind word, a smile or a funny anecdote.
“He always cared greatly for his constituents, fought hard for what he believed him and I admired his passion to improve additional learning needs policy, drawing on his experiences.
“He contributed greatly to politics in Wales, and will be missed greatly – politically and personally – in the Senedd.”
Welsh Liberal Democrat leader Jane Dodds said: “All of us at the Welsh Liberal Democrats are saddened to hear about the death of Hefin David.
“We are all thinking of his loved ones, his staff members and his community in Caerphilly.”
Labour’s Rhianon Passmore, who represents the neighbouring Islwyn constituency, wrote: “No form of words can accurately express the sense of loss I feel for my friend Hefin.
“A loving father and astute politician, he was a communicator of talent and a true fighter for his constituents. Rest in peace my friend.”
Her colleague Mick Antoniw agreed: “He was a fine communicator, with a sharp intellect and sense of humour, and he was a strong advocate for autistic and disabled people.
“He will be truly missed.”
Andrew Morgan, leader of the Welsh Local Government Association (WLGA), the voice of Wales’ 22 councils, added his voice to a chorus of tributes.
He said: “As a local government family, we are deeply saddened by the news of the untimely passing of Hefin David. Since his election in 2016, he had been a staunch representative for his community and had also been an active member of Caerphilly council for many years.
“At local and national levels, Hefin was a thoughtful and fearless politician whose loss will be keenly felt on the Senedd’s backbenches.
“On behalf of the WLGA, I extend my sincere condolences to his family, friends and colleagues at this saddest of times.”