Former Sheriff Joe Arpaio, for years a fearsome figure for Arizona’s Latinos, was convicted of criminal contempt this week for violating a court order to stop his dragnet harassment of immigrants for documentation.

The misdemeanor conviction, which could mean six months in jail, should be a warning against the kinds of abusive tactics used by Sheriff Arpaio in his self-appointed role as guardian and enforcer of federal immigration law — an effort the Justice Department called one of the worst examples of racial profiling it had ever seen. But so far the message appears to have fallen on deaf ears; unchastened, Immigration and Customs Enforcement (ICE) appears to have little trouble finding local police departments willing to join President Trump’s aggressive national search for potential deportees.

This week in Texas, Thomas Homan, the acting director of ICE, praised President Trump for taking “handcuffs” off ICE agents as he welcomed 18 Texas county sheriffs into agreements under which local deputies will be trained to enforce federal immigration laws. “The days of turning our head the other way are over,” Mr. Homan said. “President Trump said we are going to enforce the law.”

ICE’s move to enlist county sheriffs’ departments for immigration enforcement is gaining particular momentum in Texas, which accounts for nearly a third of the 60 deals signed so far by local police units in a surging federal program.