Described as an "anti-mining activist", Pérez has been involved in protests against water privatization efforts and the proposed Kimsacocha mining project,[5] which led to him being charged with terrorism.

During his tenure as Prefect, Pérez prioritized environmental and water policy, carrying out reforestation, promoting bicycle use in the province, and pushing to eliminate single-use plastic bags.

[18][19] Pérez rose to national prominence for his role in the 2019 demonstrations against the neoliberal economic policies of President Lenín Moreno.

[20] Pérez belonged to the indigenous political party, Pachakutik, and defended a "flexible and open left", hostile to the policies of Rafael Correa.

[22] This was considered a surprising result, as unreliable and possibly biased pre-election polling had put Pérez in third place, behind Arauz and right-wing banker Guillermo Lasso.

[24] On 19 May 2021, Pérez left Pachakutik in disagreement over the party's legislators working together with CREO to elect the new speaker of the National Assembly.