Illegality in English law is a potential ground in English contract law, tort, trusts or UK company law for a court to refuse to enforce an obligation. The illegality of a transaction, either because of public policy under the common law, or because of legislation, potentially means no action directly concerning the deal will be heard by the courts. The doctrine is reminiscent of the Latin phrase "Ex turpi causa non oritur actio", meaning "no cause of action arises from a wrong". The primary problem arising when courts refuse to enforce an agreement is the extent to which an innocent party may recover any property already conveyed through the transaction. Hence, illegality raises important questions for English unjust enrichment law.