St. Eustatius has a civil law system. The main body of civil law is the Civil Code. In the years to come the applicable former Netherlands Antilles legislation on St. Eustatius will gradually be replaced by Dutch legislation. Currently, there are different types of legislation applicable on St. Eustatius:
- International acts and treaties;
- Kingdom Acts;
- Dutch law especially written for the BES islands;
- Former Netherlands Antilles law, which was adjusted to be applicable on St. Eustatius, Saba and Bonaire in order to limit the impact of the transition as of 10 October 2010. Currently this is larger part of the legislation on St. Eustatius, however, within the coming years this will be gradually replaced by new legislation; and
- Local legislation (Island Ordinances and Island Decrees).
The Joint Court of Justice does not have a seat or a court registry in St. Eustatius. For the delivery of documents or the payment of legal charges the court registry is established in St. Maarten. However, once a month (usually on a Tuesday) there is a session of the Court of First Instance in St. Eustatius. These sessions are held at the government administration building located in Oranjestad. During these sessions both civil and criminal cases are handled. The Court of Appeal of Aruba, Curacao, St. Maarten, Bonaire, St. Eustatius and Saba is established in St. Maarten. The Supreme Court for St. Eustatius is the Supreme Court in The Hague (Hoge Raad), the Netherlands, which is also the Supreme Court for Aruba, Curacao, St. Maarten, Bonaire, St. Eustatius and the Netherlands.
As is the case in the Netherlands, the principles of “reasonableness and fairness” (redelijkheid en billijkheid) are an important factor in the civil relations between parties. Contracts can be enforced, both when they are merely oral or when put in writing. The Civil Code offers important protection to relatively vulnerable parties in contractual relations, such as employees in labor law and consumers when buying goods or acquiring services from professional providers.