ICE reveals legal theory behind warrantless immigration arrests

The top official at Immigration and Customs Enforcement made clear to federal agents in a new memo that they can make snap decisions to arrest suspected illegal immigrants without a warrant under certain conditions.

The memo, which the government filed in federal court on Friday as part of a case in Minnesota, broadens ICE’s view of warrantless arrests. Acting Director Todd Lyons suggested that previously, the agency had been interpreting the law incorrectly.

When ICE agents make civil immigration arrests...