There’s self-censorship, and there’s self-censorship that comes after knowledge of state surveillance:
….There is little media regulation and zero artistic censorship. But in the name of protecting the state from organized crime, the government has introduced various edicts and laws that could affect the rights of citizens.
In March 2012, the Mexican Congress approved new legislation that gave police more access to online information. Also between 2011 and 2012, the Secretariat of National Defense, which controls the Mexican Armed Forces, purchased advanced domestic surveillance equipment. The new equipment includes mobile phone and online communications software that can be openly used to monitor Mexican citizens….
Via Mexico: Freedom of expression hobbled by self-censorship @ Index on Censorship.