On September 1st, 2026, the Mexican Congress convened its latest legislative session.
The Mexican Congress has two chambers, the Senado and the Cámara de Diputados. The lower house is the Cámara de Diputados, the Chamber of Deputies, equivalent to the U.S. House of Representatives. It has 500 representatives. The terms for this chamber are 3 years.
The Cámara de Diputados meets here in the Palacio Legislativo de San Lázaro:

The upper house is the Senado, the Senate, equivalent to the U.S. Senate. It has 128 senators.
Mexican senators, like those in the U.S., have 6-year terms. The Mexican Senate meets here:

Senator Enrique Inzunza Cazarez is one of the Sinaloa Ten indicted by a U.S. federal court for collusion with the Chapitos faction of the Sinaloa Cartel. Two are now in U.S. custody.
Senator Inzunza has shown up for the legislative term. On August 26, Inzunza announced his departure from the MORENA party delegation of the Senate, to become an independent senator. (See Senator Inzunza Not in Detention, Still a Mexican Senator). But he is still in the Senate and said he will still vote with the MORENA party.
Here’s a photo of Senator Inzunza on the day of his return to the Senate, August 31st, the day before the full session began:
