An anticipated constitutional showdown between lawmakers and a panel appointed by Governor Andrew Cuomo to clean up state government took root Wednesday when the New York State Senate Republican Campaign Committee moved to quash a subpoena seeking information on its campaign donors and housekeeping account.

The motion to quash, which was filed in Manhattan Supreme Court and alleges that the Moreland Commission subpoena is overbroad, unconstitutional and “tainted by impermissible partisan bias,” is the first direct legal challenge to the panel’s authority.