Immigration street sweeps led to more ‘collateral’ arrests of noncriminals

A quarter of immigration arrests since August were labeled by U.S. Immigration and Customs Enforcement as “collateral,” a type of arrest and detention that’s been challenged in court as an end run around civil rights.

Public outrage and lawsuits over the arrests may be tamping down the large-scale sweeps that foster them, but tens of thousands were arrested this way between August and early March.

Immigration arrests are usually based on warrants obtained ahead of time, showing either...