This text provides a critical review of the way in which access to public information began to be more open in Mexican states, as a result of the first state legislation on the matter. It compares the various models and procedures adopted by the states in light of an original theoretical proposal. The article is divided into two parts. The first describes the theoretical assumptions supporting the three levels of analysis used to compare state laws: one concerning the normative conditions for beginning the process of opening up public infomation, another reffering to the organizational problems associated with this process and a third defining the jurisdictional sphere. I the second part, ten criteria drwn from these three levels of analysis are used to undertake a critical comparison of the status of access to public infomation in the Mexican federal regime. The conclusion is that this process is still incipient, incomplete and fragmented.