LOS ANGELES - A U.S. judge wants a lawyer who claims to represent Britney Spears to explain why her conservatorship belongs in federal court.

Judge Philip Gutierrez ordered lawyer Jon Eardley on Tuesday to explain by Feb. 29 why the federal court should intervene in a probate case. That came after lawyers for Spears' father, James Spears, who was named her temporary conservator Feb. 1, argued in a motion that the conservatorship should remain in state court. They argued a Superior Court commissioner had previously found the pop star did not have the capacity to retain counsel and conservatorship matters do not fall under federal jurisdiction.

Eardley filed papers Feb. 14 to move Spears' probate case to federal court, claiming the terms of the conservatorship violate her civil rights.

A message left at Eardley's office Wednesday was not returned.

The commissioner placed Spears under a conservatorship after the singer was taken to a psychiatric hospital twice this year. Conservatorships are established when a court determines someone cannot take care of themselves or their affairs. Her father and lawyer Andrew Wallet were named co-conservators of her estate.

Lawyer Jeffrey Wexler also asked the judge to require Eardley to pay James Spears' lawyer fees and any extra expenses caused by the removal of the case to federal court, and to disclose the names of anyone he worked with on the case.