We discuss the ungrammaticality of Spanish impersonal se (Impse) in combination with another se in control structures. Our main goal is to critically evaluate Martins & Nunes’s (2017) account of parallel phenomena in European Portuguese, who, adopting a movement theory of control, claim that Impse merges in the external argument of the non-finite embedded verb and moves to the matrix clause. When Impse and the other se are transferred within the same phase, the result is ungrammaticality due to an identity violation. We illustrate that their approach cannot be extended to Spanish. Instead, we put forth MacDonald & Vázquez-Lozares’s (2021) proposal as an alternative, which as we show allows for an extension to ungrammatical contexts in which the identity of se cannot be appealed to.