In civil lawsuits, a plaintiff seeks compensation from the defendant for some injury allegedly caused by the defendant. The typical relief sought is money damages. There are several ways to measure money damages. A plaintiff's expectation damages, for example, is the amount of money the plaintiff expected to receive had the defendant not breached or otherwise damaged the plaintiff. Restitution damages, on the other hand, seek to remove some ill-gotten benefit bestowed on the defendant from the plaintiff.
Calculate the amount of money the plaintiff bestowed on the defendant. For example, assume the plaintiff delivered five crates of car parts to the defendant's auto shop. Add up the amount of the parts; here, assume it is $10,000.
Add up any payments made by the defendant. Restitution is offset by any money the defendant gave back to the plaintiff. Here, assume the defendant only paid $3,000 to the plaintiff for the shipment of car parts.
Subtract any payments made by the defendant from the total amount of gain bestowed on the defendant. Here, restitution damages would equal $7,000 because the shipment total was $10,000 and the defendant paid $3,000 to the plaintiff. The remaining $7,000 is owed to the plaintiff; it is an ill-gotten benefit if the defendant keeps the car parts without paying the plaintiff.