The common law of England and Wales applies in Gibraltar, unless otherwise provided for in locally made legislation.
Gibraltar has been a separate jurisdiction to that of the constituent countries of the United Kingdom since it was conquered in 1704.
Because of the hundreds of Acts of Parliament which have been enacted by the Gibraltarian legislature, or by Her Majesty in Council over the centuries, the body of law in Gibraltar is now significantly different, in terms of detail, to that of other common law countries.
That said, lawyers from the United Kingdom and other Commonwealth countries will find the law of Gibraltar familiar not only because of its common law foundations, but because most local enactments are similar to the ones passed in Westminster.
The Gibraltarian court system dates from Charters of Justice, made as long ago as 1740 and is separate from that of any other country, except that the final court of appeal after the Supreme Court of Gibraltar (which is the equivalent of the English High Court) and the Gibraltar Court of Appeal is the Judicial Committee of the Privy Council in London.
Court procedures closely follow those contained in the Civil Procedure Rules which regulate proceedings in England and Wales.
Possibly because of the similarities to English law, practice and procedure whilst maintaining local autonomy, the Gibraltarian jurisdiction is generally regarded as an attractive place in which to do business. This can be seen without much difficulty in the sheer number of international companies operating from Gibraltar. Certainty is the principal attribute of a properly run legal system and there is no doubt that Gibraltar provides this.