Amends the State Mandates Act. Provides that any State mandate regarding any subject matter enacted on or after the effective date of this amendatory Act that necessitates additional expenditures from local government revenues shall be void and unenforceable unless the General Assembly makes necessary appropriations to implement that mandate. Provides that the failure of the General Assembly to make necessary appropriations shall relieve the local government of the obligation to implement any State mandate. Makes conforming changes. Effective immediately.