There are two parallel systems of law operating in Brunei Darussalam: statutory laws, which regulate mercantile activities and disputes between persons, and Syariah law.
Statutory laws are generally referred to as the common law system and are based upon English codified laws. These courts are also known generally as Civil Courts and have exclusive jurisdiction over all civil and criminal cases in the country. The rules of civil procedure that are used in the higher courts are based on the Supreme Court Act Chapter 5.
An important piece of legislation is the Application of Laws Act Chapter 2. This statute stipulates that UK common law and the doctrines of equity, along with statutes of general application, as administered or in force in England prior to 25th April, 1951 shall also be in force in the Sultanate. The key proviso to this is that the said common law, doctrines of equity and statutes of general application shall only be in force so far as circumstances permit. They are also subject to be qualified by local circumstances and customs. The Contracts Act Chapter 106 and Specific Relief Act Chapter 109 embody a codified system of contract law and laws of equity based on English common law.
The second independent system of courts in Brunei Darussalam is based on Syariah law. The Syariah Penal Code Order 2013 was first introduced publicly in April 2014. Prior to the introduction of the Syariah Penal Code Order 2013, the Syariah court system had limited exclusive jurisdiction to hear and decide matters of personal law relating to persons that belong to the Islamic faith on matters pertaining to marriage, divorce, inheritance, maintenance of dependents and the estates of deceased Muslims.
The Syariah Penal Code has greatly expanded the jurisdiction of Syariah courts to now include offences such as murder, rape and theft. Such offences were previously within the jurisdiction of civil criminal courts. Brunei Darussalam now possesses an interesting criminal justice system that allows both the existing Penal Code Chapter 22 and the Syariah Penal Code Order 2013 to be in force.
Link to Syariah Penal Code Order 2013:
http://www.agc.gov.bn/AGC%20Images/LAWS/Gazette_PDF/2013/EN/Syariah%20penal%20code%20order2013.pdf
Link to Syariah Law Court Website:
https://www.e-Syariah.gov.bn/portals/Syariah/branches/web/home/index/
Link to Supreme Court Act Chapter 5:
http://www.agc.gov.bn/AGC%20Images/LOB/pdf/Cap005subR1(index).pdf