[4] Ruiz Devesa started his political career as a economic policy advisor to Jonás Fernández Álvarez, a member of the European Parliament since 2014.

In 2021 he was appointed as a member of the Parliament's delegation to the Conference on the Future of Europe.

[6] In 2022, he was the parliament's rapporteur on a proposal for an overhaul of European election rules that would give all EU citizens aged 18 and older a greater role in choosing the Commission president, allow them to vote for pan-European MEPs and choose postal voting.

[7] In addition to his committee assignments, Ruiz Devesa is a member of the European Parliament Intergroup on Climate Change, Biodiversity and Sustainable Development,[8] the European Parliament Intergroup on LGBT Rights,[9] the European Parliament Intergroup on Trade Unions[10] and the Spinelli Group.

[11] Ruiz Devesa suggested that the European Central Bank could consider helicopter money.