Anarcho-tyranny is a concept, where the state is argued to be more interested in controlling citizens so that they do not oppose the managerial class (tyranny) rather than controlling real criminals (causing anarchy). Laws are argued to be enforced only selectively, depending on what is perceived to be beneficial for the ruling elite. [ref]
In Mexico, neither the police nor the military are effective in curbing cartel violence, for a couple of reasons: plata o plombo, silver or lead. They are either bought off or simply keep a low profile because of threat of gruesome death for themselves and their families. Thus, the government has a de facto policy of either not actively discouraging or active encouraging cartel violence. On the other hand, private citizens who want to arm themselves against cartel violence find it almost impossible to do so legally because of the extremely restrictive firearms laws, which harshly punish private citizens who arm themselves for self-defense. (Indeed, communities that have done so have been harshly punished for making their communities “no go zones” for the cartels).
Anarch-tyranny: no control of real criminals, while criminalizing self-defense measures.
Example two: Chicago. No serious attempt at enforcement of Chicago’s restrictive gun laws applied against criminals who cause most of the (very large number of) firearms deaths in Chicago, while making it difficult for common citizens to legally obtain the tools (firearms) to defend themselves against predation by criminals.
You see, it is dangerous to actually attempt any sort of serious efforts to control violent criminals, but controlling common citizens who want to be law-abiding is easy-peasy. Until the tyranny becomes too much to bear, and then. . . . well, history gives us at least one clear example of a proper response.