The Internal Security Act 1960 was a preventive detention law in force in Malaysia. The legislation was enacted after the Federation of Malaya gained independence from Britain in 1957. The ISA allows for detention without trial or criminal charges under limited, legally defined circumstances. On 15 September 2011, the Prime Minister of Malaysia, Najib Razak said that this legislation will be repealed and replaced by two new laws. The ISA was replaced and repealed by the Security Offences Act 2012 which has been passed by Parliament and given the royal assent on 18 June 2012. The Act came into force on 31 July 2012.

The Security Offences Act 2012 is a controversial law supposedly "to provide for special measures relating to security offences for the purpose of maintaining public order and security and for connected matters". The Act is to replace the 1960 Internal Security Act (Malaysia). The Act was introduced by Malaysian Prime Minister Najib Razak, approved in Parliament on 17 April 2012, given the Royal Assent on 18 June 2012 and Gazetted on 22 June 2012.