Article IV, Section 4 of the U.S. Constitution”The United States shall guarantee to every State in this Union a Republican Form of Government, and shall protect each of them against invasion; and on Application of the Legislature, or of the Executive (when the Legislature cannot be convened) against domestic Violence.”Arizona sued to recoup their costs of imprisoning Mexican criminals. the case was thrown out by Judge Judith Keep in San Diego and the U.S. 9th Circuit Court of Appeals in San Francisco on grounds that California and Arizona are not being “invaded” by a hostile, foreign power.
The Constitution does not specify or require that the invasion be by a hostile foreign power. It just says “invasion”.
This should be appealed to the Supreme Court.