Member of Parliament

Dafis joined Plaid Cymru in his youth. He left the party in 1964 but rejoined in 1979.^[14]: 6 He first contested Ceredigion and Pembroke North in 1983 and finished in fourth place, a result repeated in 1987. His victory in 1992 was a notable one as he more than doubled his vote.

Dafis was a Member of Parliament for Ceredigion from 1992 until 2000, having been supported by a coalition of local Plaid Cymru and Green Party activists, the latter of which had worked with him on a number of environmental initiatives.^[15] Between 1992 and 1997 Dafis sat in Parliament as an official Plaid Cymru and Green Party MP, having been elected on a joint ticket.^[16][17] He agrees with the Greens' official recognition of Caroline Lucas as the first Green MP, as he was "a kind of hybrid, so I don't really count".^[17]

During this eight-year period as an MP, Dafis voted for homosexual law reform, against greater autonomy for schools, and for removing hereditary peers from the House of Lords.^[18][19]

Assembly Member

In 2000 he resigned as an MP to devote more time as a member of the National Assembly for Wales, to which he had been elected in 1999.

In a speech at the 2000 National Eisteddfod at Llanelli, Dafis called for a new Welsh language movement with greater powers to lobby for the Welsh language at the Assembly, UK, and EU levels.^[20] Dafis felt the needs of the language were ignored during the first year of the Assembly, and that in order to ensure a dynamic growth of the Welsh language a properly resourced strategy was needed.^[20] In his speech Dafis encouraged other Welsh language advocacy groups to work closer together creating a more favourable climate in which using Welsh was "attractive, exciting, a source of pride and a sign of strength".^[20] Dafis pointed towards efforts in areas such as Catalonia and the Basque country as successful examples to emulate.^[20]

Lord Elis-Thomas, former Plaid Cymru president, disagreed with Dafis' assessment, however. At the Urdd Eisteddfod, Lord Elis-Thomas said that there was no need for another Welsh language act, claiming that there was "enough goodwill to safeguard the language's future".^[21] His controversial comments prompted Cymdeithas yr Iaith Gymraeg to join a chorus calling for his resignation as the Assembly's presiding officer.^[21]

In 2002, Dafis announced he would step down from the Assembly at the 2003 elections, despite party leader Ieuan Wyn Jones having asked him not to do so. Soon after the elections in 2003, he announced his candidacy for Presidency of the party, but lost to Dafydd Iwan.