WASHINGTON (AP) — A federal judge seems skeptical of a lawsuit that seeks to halt President Barack Obama's immigration plan to spare nearly 5 million people from deportation.

U.S. District Judge Beryl Howell heard arguments Monday in a case brought by an Arizona sheriff who claims the program will let more illegal immigrants enter the country and commit crimes, burdening law enforcement.

Howell repeatedly questioned whether Maricopa County Sheriff Joe Arpaio has legal standing to challenge Obama's action. She told Apraio's attorney Larry Klayman that Congress is in a better position to question the president's authority rather than a federal court.

A lawyer for the Obama administration called Arpaio's case a "political dispute" that should be dismissed.

Howell said she would issue a ruling soon.