Generally, the courts have stated that they will not lend their aid to a person whose claim is based upon an immoral or illegal act.
However, the courts may lend aid to a person whose contract has some immoral/illegal aspect where such person is not themselves involved in the immoral/illegal act. For example, in Holman v Johnson (1775), the Plaintiff contracted and delivered tea to the Defendant knowing that it was being bought for the purposes of smuggling. The Plaintiff sues for the breach of contract after the Defendant failed to pay for the tea. The Defendant argued that this contract was void as against public policy.
The court held in favor for the Plaintiff who was entitled to recover. The plaintiff had not committed an offense as delivery and sale of the tea were legal activities that occurred prior to the proposed smuggling plan, and the plaintiff’s contract was complete once the goods had been delivered. The Plaintiff was not involved in the smuggling operation post-deliver, and therefore had not entered into a contract for an illegal/immoral purpose.