In 1998, President Ernesto Zedillo, on the 30th anniversary of the Tlatelolco massacre, authorized a congressional investigation into the events of October 2. However, the PRI government continued its recalcitrance and did not release official government documents pertaining to the incident.
Enduring questions remained after "La Noche Triste" (the Sad Night) that have taken the Mexican government over 30 years to answer.