A lawsuit seeking a declaratory judgment—also known as a “deck action” (dec. action)—is a lawsuit that asks the court to determine the rights, status, or other legal relations of the parties when a controversy has arisen, but before a wrong has been committed. A declaratory judgment seeks to prevent further litigation, liability, and harm. Declaratory relief is not available to settle disputes already pending before a court. A declaratory judgment is improper if the relief requested is raised for the first time in an amended petition (lawsuit) and merely addresses the same issues as were raised in the original petition.

A declaratory judgment is often sought when there is a disagreement over the meaning or application of an insurance policy or other contract, or a deed, will, trust, lease, statute, or municipal ordinance.

In Illinois, a declaratory judgment action, or 'dec action,' is a legal proceeding in which a party seeks a court's determination on the legal rights, duties, or status of the parties involved, typically when a controversy exists but no actual harm or wrong has yet occurred. This type of action is used to clarify legal relationships and to prevent or limit future litigation, liability, or harm. Under Illinois law, declaratory relief is not intended to resolve disputes that are already being litigated in court. Furthermore, a declaratory judgment is not appropriate if it is requested for the first time in an amended petition that does not present new issues but rather revisits the same matters addressed in the original filing. Declaratory judgments are commonly pursued in cases involving uncertainties in contracts, insurance policies, deeds, wills, trusts, leases, statutes, or municipal ordinances. The Illinois Declaratory Judgment Act, found in 735 ILCS 5/2-701, governs the use of declaratory judgments in the state and outlines the circumstances under which such relief may be sought.