If taxpayers want to curb pension costs with a ballot measure, do they need an OK from unions before they start collecting signatures? San Diego’s Municipal Employees Association seems to think so. The MEA, which represents 6,000 workers on the city payroll, wants government unions to have a gatekeeper role in the initiative process — a right to advance review of certain ballot proposals that would affect employee benefits. Disturbingly, the courts have declined, so far, to set the union straight.
 
 Triggering the controversy is Proposition B, the pension-reform plan that San Diego voters overwhelmingly approved on June 5....