Have your passport and visa ready. Less than an hour later, between Amatenango de La Valle and before Teopisca, the Federal Judicial Police often have a roadblock. An hour later, entering San Cristobal, one passes the massive military base at Rancho Nuevo, and a state police checkpoint. On the other side of the city, heading North, is another inspection point by military soldiers. There are four late night dance clubs and a red-light district where the white powder flows freely.
Some tourists end up entrapped and are arrested for drug possession.
They don't generally end up in the State Penitentiary at Cerro Hueco. They found neither peace observers nor Italians. The international observers all receive training and advice to avoid these bars precisely because of the rampant presence of informants and police. They did find one North American anthropologist with two grams of cocaine. He was with a North America freelance reporter who herself was in a state, according to people who saw her that night, of extreme enebriation.