The 1925 constitution did not allow a person to be president for two consecutive terms. The incumbent president, Eduardo Frei Montalva, was therefore ineligible as a candidate. The CIA's "Track I" operation was a plan to influence the Congress to choose Alessandri, who would resign after a short time in office, forcing a second election. Frei would then be eligible to run. Alessandri announced on 9 September that if Congress chose him, he would resign. Allende signed a Statute of Constitutional Guarantees, which stated that he would follow the constitution during his presidency trying to shore up support for his candidacy. Congress then decided on Allende.