Local Government Antitrust Act of 1984

Local Government Antitrust Act of 1984 - Declares that the antitrust laws shall not apply to official conduct of a local government reasonably undertaken to protect or provide for the public health, safety, or welfare. Limits the amount a person or State may recover on a claim under the antitrust laws based on any other official conduct of a local government to the amount of actual damages sustained, interest thereon, and the cost of suit, including a reasonable attorney's fee. Requires interest on damages to be awarded for the period: (1) beginning on the date of filing of the claim and ending on the date of judgment unless the court finds that the award of all or part of such interest is unjust; and (2) beginning on the date of injury and ending one day before the claim is filed if the court finds that the award of all or part of such interest is just.

Directs the court to award the cost of suit to the substantially prevailing party in an antitrust action based on the official conduct of a local government. Allows such award to be reduced or withheld in the interest of justice. Provides that no official, employee, or agent of such local government shall be personally liable for damages, costs, interest, or attorney's fees in such an action.