[1][2][3] He is a member of the Catalan independentist party Republican Left of Catalonia (ERC).

Benach worked for the Catalan Generalitat as a sweeper after he left university.

He has also co-written República catalana (Catalan Republic) and Educar en política (Teaching in politics).

In 1987 he joined the ERC, where he served as general vice-secretary of institutional politics.

[4] He has been a deputy in the Catalan Parliament since 1992, where he served as second secretary of the board (1999–2003) and president.