Face to Face I have had US consulates give me absolutely bogus information to the point where I ignore them whenever possible. The role of a consular agent is to process passport information and pass out lists of physicians and Mexican attorneys who have been "approved". They visit the incarcerated.
When "Elizabeth" ran the Ixtapa consulate she explained to me "Positively no one but a Mexican IMN agent can demand to see your FMM or resident's papers".
UTTERLY FALSE
I read the words with out of the large black codebook carried by the SSP comandante of the Petlatlan Office of the SSP, I spent hours sitting on a tailgate of of policia federal going over the codebook with a polite senor Joaquin.
Any designated Law Enforcement Agent has the law behind them when they ask to see your immigration paperwork. There is no gray area. Printed on paper in perfectly clear Spanish the federal Article 42 provision is unmistakable. How anyone interprets and enforces this law is a horse of another color.
Another example: The Nogales consulate put out public warnings about "Unannounced Road Blocks" existing on the Sonoyta / Puerto Penasco highway. The jefe in the Sonoyta SSP office bristled when I showed him the warning.
"Let us put up billboards and take out newspaper ads to announce to everyone when we erect a "reten". This should make the bad people very happy!" The foregoing is verbatim.
If your Spanish is good, and you approach SSP regional offices politely exhibiting a mood to learn correct Mexican law, these guys will **** near fall over each other trying to help a person learn.
The days of the surly PJF (Policia Judicial Federal) are ancient history.
"Is it possible for you to show me exactly where....?" spoken in a nice tone with a smile is darned near magic. I have done this in more than a dozen offices and have never been treated anything other than with extreme politeness. The "I want to learn" tactic opens doors.