The legal battle over Immigration and Customs Enforcement officer Christian Castro — charged with a crime in Minnesota before returning to Texas — has become a test of a little-discussed constitutional provision.

Castro, a federal immigration officer, is accused of shooting Julio Cesar Sosa-Celis in Minneapolis on Jan. 14 while pursuing another man during an immigration enforcement operation. Minnesota prosecutors charged Castro with four counts of second-degree assault with a dangerous weapon and one count of falsely reporting a crime.