California Code, Corporations Code - CORP § 18270

(1) A writ of execution on the judgment against the unincorporated association has been returned unsatisfied in whole or in part.

(2) The unincorporated association is a debtor in bankruptcy.

(3) The member, director, officer, or agent has agreed that the creditor need not exhaust the assets of the unincorporated association.

(4) A court grants permission to the judgment creditor to levy execution against the assets of a member, director, officer, or agent based on a finding that the assets of the unincorporated association subject to execution are clearly insufficient to satisfy the judgment, that exhaustion of the assets of the unincorporated association is excessively burdensome, or that the grant of permission is an appropriate exercise of the court's equitable powers.