[6] For most of the 19th century the criminal law which applied in the Straits Settlements (comprising Prince of Wales' Island (Penang), Singapore and Malacca) was that of the United Kingdom, insofar as local circumstances permitted.

However, due to problems such as doubts as to the applicability of Indian Acts, in 1871 the Straits Settlements Penal Code 1871[7] was enacted.

Upon engaging a lawyer (defence counsel), the defence counsel will make written representations without prejudice legally to the prosecuting authority, the Prosecution may then review, exercise his prosecutorial discretion,[10] and consent to amend the charge with lesser relevant offence, a process known as plea bargaining.

This is where the defence counsels will engage without prejudice with the Public Prosecutor in negotiations for reduction of charges, or mitigation in plea to seek leniency from the Court.

In 2006, the Ministry of Home Affairs (MHA), in consultation with the Attorney-General's Chambers, Ministry of Law and other agencies, conducted an extensive review of the Penal Code in order to bring it "up to date, and make it more effective in maintaining a safe and secure society in today's context".