In 1815 Paso was named assistant to the Supreme Director and war consultant. He was later elected a representative to the Congress of Tucumán that declared the Argentine Independence on July 9, 1816. As Secretary to this Congress, Paso had the honor of reading the independence act. However, he was then imprisoned and charged of treason for supporting the monarchist faction that wanted a monarchy as government for the new nation. He was quickly released along with the other monarchist deputies.