A cluster of lookouts in an Arizona neighborhood have started sending blast text messages to warn when an immigration sweep is imminent. Who are they on the look out for? The cop Reason loves to hate, of course—Maricopa county sheriff Joe Arpaio.

You remember Arpaio: He's the anti-illegal immigration zealot who forced prisoners to live in tents in the desert, held a candlelight vigil for his deputies when they were imprisoned after being caught on tape stealing documents in a courtroom, retaliated against newspapers that did investigations on him (also against mayors who speak against him), inspired a life-sized guerilla art installation at the Mexican border, and left a Hispanic woman arrested after a traffic stop in shackles while she gave birth.

Frankly, I'd subscribe to text messages warning me when this guy is coming.

Lydia Guzman, director of the nonprofit immigrant advocacy group Respect/Respeto, is the trunk of a sophisticated texting tree designed to alert thousands of people within minutes to the details of the sweeps, which critics contend are an excuse to round up illegal immigrants.

Guzman said the messages are part of an effort to protect Latinos and others from becoming victims of racial profiling by sheriff's deputies. Deputies have been accused of stopping Hispanics, including citizens and legal immigrants, for minor traffic violations to check their immigration status....

Arpaio has conducted 13 sweeps since March 2008, and deputies have arrested 669 people, about half of whom were held on immigration violations.

Eugene Volokh, who alerted me to this story, has a paper [PDF] on crime-facilitating speech with some relevant case law. He asks the tough questions:

So what’s the First-Amendment-relevant difference, if there is one, between this and a lookout who alerts criminals when the police are coming? (Assume that the lookout isn’t getting a share of the loot, but is just helping his friends avoid getting locked up.) Should it matter, as one expert who’s mentioned in the article suggests, whether Ms. Guzman’s real goal is preventing lawful arrest of illegal immigrants (as opposed to preventing racial profiling, assuming such profiling is unlawful)?