DETROIT -- Michigan Attorney General Mike Cox has filed a legal brief on behalf of nine states supporting Arizona's immigration law.

The Republican gubernatorial candidate said Wednesday that Michigan is the lead state backing Arizona in federal court. Michigan is joined by Alabama, Florida, Nebraska, Pennsylvania, South Carolina, South Dakota, Texas and Virginia, as well as the Northern Mariana Islands.

Cox says states have the authority to enforce immigration laws and protect their borders.

The Arizona law would require state and local police to question and possibly arrest illegal immigrants during the enforcement of other laws such as traffic stops.

President Barack Obama's administration recently filed suit to block it, saying immigration is a federal issue.