In 1913, after Henry Lane Wilson supported Victoriano Huerta's coup, he was apprehended by the new regime and, along Nicéforo Zambrano, Alfredo Pérez and other Maderista militants, lead to Mexico City.

Deported to the United States, Siller resided in that country without breaking away from the enemy military fronts against Huerta's usurping government.

Once organized the constitutionalist movement, he crossed the border and later joined the forces of Pablo González Garza and Antonio I. Villarreal, later those of Lucio Blanco.

Later, and with his personal budget, he founded and presided over the Progressive Constitutional Party, platform by means of which impelled the campaign for governor of Nicéforo Zambrano that obtained the triumph.

Substitute mayor in 1917 and the following year proprietary municipal president of Monterrey, in 1925 Siller was appointed temporary governor replacing Porfirio G. González that had been under riot act.