ANANDA SHOREY
Associated Press Writer

PHOENIX - A group supporting a voter-approved initiative aimed at keeping illegal immigrants from obtaining some government services filed a motion in U.S. District Court in Tucson to be allowed to help defend the measure.

A lawyer for Protect Arizona Now filed the motion Monday to intervene in the lawsuit the Mexican American Legal Defense and Educational Fund filed Nov. 30.

The lawsuit argues that Proposition 200 is unconstitutional because it usurps the U.S. government's power over immigration.

Protect Arizona Now's director, Kathy McKee, said the group filed the motion because it doesn't trust the state to defend the measure.

The proposition requires proof of immigration status when obtaining certain government services and proof of citizenship when registering to vote. Government workers who don't report illegal immigrants could face jail time and a fine.