If your friend has been acquitted of a false criminal case, they may be able to file a damages claim for malicious prosecution. This can be pursued under Section 211 of the Indian Penal Code (IPC), which deals with false charges, and is linked to defamation under Section 499. You can choose to pursue either a civil claim for compensation or a criminal case, or both, once malice is established. It's crucial to consult with a lawyer to determine the best course of action based on the specifics of the case and your desired outcome.