Quick Take Close to 4,000 employees of the California Department of Public Health were told they must use the federal E-Verify system to keep federal funding. About 4,000 California Department of Public Health employees have been told they must use a federal verification system to prove they’re U.S. citizens. As at other U.S. employers, all new California health department employees complete a federal I-9 form to prove their citizenship. Walls told CalMatters the health agency is currently the only California state department the union is aware of that has asked their employees to recertify their citizenship status. The union represents about 100,000 state employees at 140 state agencies, boards, commissions and departments.