Internal Security Act

Singapore Infopedia


The Internal Security Act (ISA) is a law that enables the government to swiftly act against what it deems to be threats to national security by employing various measures. The law is carried out by the Internal Security Department (ISD), a body under the purview of the Ministry of Home Affairs. The key power of the ISA is the placing of an individual under preventive detention for a renewable period of up to two years at a time without trial in open court. The government justifies the law on the grounds of preserving public order and safety, and states that it is used only as a last resort. Since it was commenced in 1963, the ISA has been used to deal with national security issues such as communalism, communism, espionage, foreign subversion and terrorism.1 Despite calls for its abolishment, the government has defended the continued relevance of the ISA in Singapore in the face of an evolving security landscape.2

The origins of the ISA can be traced to the Emergency Regulations enacted in 1948 – a temporary provision that was subject to continual review and reissuance. The regulations empowered the British colonial authorities in Singapore to combat the communist insurgents during the Malayan Emergency, which lasted from 1948 to 1960. In October 1955, the Labour Front government led by then Chief Minister David Marshall replaced the Emergency Regulations with the Preservation of Public Security Ordinance, which extended the duration of an individual’s detention to up to two years. The new law was enacted in response to a series of strikes and riots that had occurred in 1954 and 1955, including the National Service riots and the Hock Lee bus riots.3 The Federation of Malaya enacted the ISA to replace the Emergency Regulations in 1960, and when Singapore became a part of the Federation of Malaysia on 16 September 1963, an amended version of Malaysia’s ISA was extended to Singapore. The legislation was retained after Singapore gained independence on 9 August 1965.4

Powers granted by the ISA
One of the main powers granted by the ISA is preventive detention. It allows the government to detain an individual who is suspected of being a threat to Singapore’s internal security for a maximum period of 30 days. Thereafter, an Order of Detention has to be issued in order to extend the detention period to a maximum of two years. If the offence is deemed not too severe, a Restriction Order can be issued instead, under which the individual is released but still subjected to certain restrictions such as having to seek permission to travel abroad. Both the Order of Detention and the Restriction Order can be renewed when necessary. Other powers of the ISA include the prosecution of those who disseminate misinformation to stir up public anxiety, and the imposition of curfews to calm public disorder.5

Role of the judiciary
The ISA was amended in 1989 to abolish judicial reviews as well as appeals to the Privy Council. Henceforth, with the exception of procedural matters, government decisions taken under the ISA are not subject to questioning by any court of law. The amendments stemmed from a case in 1971 in which four ISA detainees were released on a legal technicality following a ruling by the Court of Appeal. The four were, however, served with new orders and immediately rearrested.6

To prevent the abuse of powers provided by the ISA, there are mechanisms to define the legal limits, requirements and accountabilities of the legislature. For instance, an Order of Detention has to be authorised by the minister for home affairs and approved by the president in order to detain an individual for a period beyond 30 days and not exceeding two years. Each Order of Detention or Restriction Order must be reviewed by an independent ISA advisory board composed of a Supreme Court judge and two prominent citizens appointed by the president in consultation with the chief justice. The board functions like a court of law, and detainees may seek representation from legal counsel to defend their case before the board. The board would then submit its recommendations to the president for approval.7

In addition, certain basic rights of detainees are retained under the ISA. These include the observance of religious obligations as well as access to legal counsel, family members and doctors. A detainee under the Order of Detention also has to be informed of the grounds on which he/she is charged and has the right to dispute the order with the ISA advisory board.8

Instances of ISA being invoked
Threat of communalism
In 1987, four Malay men were detained under the ISA for spreading rumours of impending racial clashes in Singapore and making preparations for such clashes. Three of the four men were found to have undergone training from Budi Suci Sejati, a spiritual silat (a form of Malay martial arts) group based in Johor, Malaysia. The leaders of the silat group were said to have encouraged the men to recruit more followers in Singapore and promised to assist them if racial clashes broke out.9

Publication of incendiary materials
In 1971, four top executives of the Chinese newspaper Nanyang Siang Pau were detained under the ISA for fomenting feelings of resentment among the Chinese community against the government. The arrests came after the executives were accused of adopting an editorial policy of “glamorising the communist system and working up communal emotions over Chinese language and culture”.10

Six years later, a former correspondent of Hong Kong-based magazine Far Eastern Economic Review (FEER), Ho Kwon Ping, was arrested under the ISA and placed in solitary confinement for two months for writing pro-communist articles that discredited the government. Ho later confessed that he had used disinformation to portray the government as “elitist, racialist, fascist, oppressive and dictatorial” in the articles published in FEER.11

Threat of communism
In 1963, Operation Coldstore was launched against members of the Barisan Sosialis, a left-wing opposition political party allegedly involved in communist activities against the government. Several key leaders of the Barisan Sosialis were detained under the Preservation of Public Security Ordinance.12 The government led a further crackdown on the Barisan party members in 1966 for attempting to organise islandwide anti-America demonstrations in response to then President of the United States Lyndon B. Johnson’s visit to Malaysia.13 Chia Thye Poh, a former Barisan leader who was arrested under this crackdown, remains the longest-held ISA detainee: He was detained for 23 years and served nearly a decade on Restriction Order until his complete release in 1989.14 Through the years, Chia has denied the governments charge of his alleged involvement with communists.15

In 1987, the ISD launched Operation Spectrum against what it claimed was a Marxist conspiracy targeted at overthrowing the government in order to establish a communist state in Singapore. Twenty-two individuals were arrested under the ISA for allegedly infiltrating and subverting religious social-service organisations and student groups, as well as professional bodies, so as to bring about radical change.16

Threat of espionage
Between 1997 and 1998, there were two instances in which Singaporeans were reportedly involved in spying for foreign intelligence agencies. A total of six people were detained under the ISA in the two incidents for their alleged involvement in espionage and have since been released.17

Threat of foreign interference
On 6 May 1988, lawyer and political activist Francis Seow was detained under the ISA as part of government investigations into foreign interference in Singapore's domestic politics. He was released from detention in July that same year, with restrictions placed on his overseas travel and contact with representatives of foreign governments.18

Threat of terrorism
In 1985, the ISA was used to detain two Singaporean men for their involvement in smuggling weapons and explosives to the Tamil Tigers, a Sri Lankan separatist group. Following further investigations by the ISD, a group of Sri Lankan professionals in Singapore were deported for allegedly supporting the Tamil separatist movement in their homeland.19

In December 2001, the ISD arrested 15 people, 13 of whom were believed to be members of the radical Islamic group, Jemaah Islamiyah (JI), which was planning a series of bomb attacks in Singapore. The 13 JI members were eventually detained under the ISA for their involvement in the bomb plot, while the remaining two were released in January 2002 on Restriction Orders.20 The JI members were allegedly planning to attack several embassies, naval bases and commercial buildings that house American companies in Singapore. They also targeted local installations and sought to sow discord between Singapore and Malaysia in the ensuing chaos.21 The arrests conducted under the ISA enabled the government to cripple the JI network before its plans could be carried out.22

In 2006, Mas Selamat bin Kastari, the head of the Singapore branch of JI, was arrested in Indonesia and subsequently extradited to Singapore where he was detained under the ISA at the Whitley Road Detention Centre. He escaped from detention in 2008 but was subsequently recaptured by the Malaysian authorities a year later and eventually sent back to Singapore for detention in 2010.23

In 2010, Muhammad Fadil Abdul Hamid, then a national serviceman, was arrested and detained under the ISA for attempting to embark on terrorist-related activities overseas. He was said to be part of an emerging trend of “self-radicalised” individuals who were attracted to terrorist activities after being exposed to terrorist propaganda on the Internet.24

In 2012, two senior JI members who had been on the run since fleeing Singapore in 2001 were detained under the ISA. The first member, Husaini Ismail, had been arrested and jailed in Indonesia in 2009; he was detained by the ISD upon his deportation back to Singapore following his release. He was believed to have been involved in a plot by Mas Selamat to crash a plane into Changi Airport in 2002. The other member, Abd Rahim Abdul Rahman, was arrested in Malaysia in February 2012 and deported back to Singapore.25

In 2013, Masyhadi Mas Selamat, the eldest son of former JI leader Mas Selamat bin Kastari, was arrested by Indonesian police in Central Java and deported back to Singapore. He was subsequently placed on a two-year detention order under the ISA for his alleged involvement in terrorist-related activities.26

Opposition to the ISA
The ISA has been criticised by local opposition parties for its extensive powers that make it vulnerable to abuse. The issue of whether to abolish or retain the ISA was hotly debated in both the general election and presidential election held in 2011.27 Human-rights and local civil-society groups have also criticised the ISA, accusing it of infringement of human rights. Calls to abolish the ISA in Singapore ensued following Malaysia’s decision to repeal its ISA in 2011.28

A key criticism levelled against the ISA is that it has become a tool for the government to stifle political dissidents and opponents. The detentions of key Barisan leaders, Marxist conspirators and Francis Seow have constituted some of the most cited instances of alleged political suppression under the ISA.29

Former detainees have also accused the safeguards on the ISA of being ineffectual. They have, for instance, questioned the autonomy of the advisory board, lamented the judiciary’s inability to check the executive, and complained of ill-treatment.30

There have been calls to replace the ISA with an anti-terrorism law, so as to deal with the latent terrorist threat while preventing any politically motivated arrests from being made under the ISA.31

Support for the ISA
The government believes that the ISA is still highly relevant to Singapore’s security landscape. Besides terrorism, the government has pointed to other existing threats to national security, such as foreign subversion, espionage and acts of violence or hatred using race and religion. As such, the government feels that there is a need for the ISA to be retained, as it allows the authorities to act promptly and swiftly against elements that are threatening the nation’s security.32

Although the government has rejected suggestions to replace the ISA with an anti-terrorism law, it remains open to possible changes to the ISA in the future to reflect changing times and circumstances.33

The government acknowledges the extensive powers of the ISA, therefore it believes that preventive detention should only be used as a last resort. The government has in fact used the ISA sparingly in recent years, with most detentions involving suspected terrorists. Furthermore, the government is confident that the safeguards that have been put in place to prevent the abuse of the ISA are rigorous and effective.34

Terence Foo

1. Tommy Koh et al., eds., Singapore: The Encyclopedia (Singapore: Editions Didier Millet and National Heritage Board, 2006), 255 (Call no. RSING 959.57003 SIN-[HIS]); Ministry of Home Affairs, Singapore, A Singapore Safe For All (Singapore:  Times Books International, November 2002), 15–17; Damien Chong, “Selling Security: The War on Terrorism and the Internal Security Act of Singapore,” 
Copenhagen Journal of Asian Studies 23, no. 1 (2006): 33. 
2. “ISA Is Needed Now More Than Ever,” Straits Times, 20 October 2011, 32. (From NewspaperSG)
3. Koh et al., Singapore: The Encyclopedia, 175, 255; Legislative Assembly, Singapore, Second Reading of the Preservation of Public Security Bill, vol. 1 of Debates: Official Report, 21 September 1955, cols. 695–6, 704, 749 (Call no. RCLOS 328.5957 SIN); Legislative Assembly, Singapore, Considered in Committee, Reported and Third Reading of the Preservation of Public Security Bill, vol. 1 of Debates: Official Report, 12 October 1955, cols. 823, 839, 856. (Call no. RCLOS 328.5957 SIN)
4. Koh et al., Singapore: The Encyclopedia, 175, 255; Ministry of Home Affairs, Singapore, Singapore Safe For All, 17.
5. “ISA Is Needed Now More Than Ever”; Ministry of Home Affairs, Singapore, Singapore Safe For All, 15, 21, 24–25.
6. Melanie Chew, “Human Rights in Singapore: Perceptions and Problems,” Asian Survey 34, no. 11 (November 1994): 943 (From JSTOR via NLB’s eResources website); “ISA Detainees Re-Arrested after Release on Technicality,” Straits Times, 9 December 1988, 1; “Amendments to Internal Security Act Come into Effect,” Straits Times, 31 January 1989, 1. (From NewspaperSG)
7. Ministry of Home Affairs, Singapore, Singapore Safe For All, 24–25.
8. Ministry of Home Affairs, Singapore, Singapore Safe For All, 26–27.
9. “Four Silat Detainees Had Special Training in Johor,” Straits Times, 30 July 1987, 13; Yaakub Rashid, “Silat Stance,” Straits Times, 31 October 1991, 11. (From NewspaperSG)
10. “A Nanyang ‘Confession’,” Straits Times, 23 May 1971, 1. (From NewspaperSG)
11. Ministry of Culture, “The Internal Security Department Detained Ho Kwon Ping, Former Correspondent for the Far Eastern Economic Review (FEER) on March 12, 1977,” press release, 16 April 1977 (From National Archives of Singapore document no. 777-1977-04-16); R. Chandran, “Free Hand for Anti-Govt Stories,” Straits Times, 18 April 1977, 1; Wong Kim Hoh, “Who Says I Sold Out?” Straits Times, 11 January 2004, 42. (From NewspaperSG)
12. Hong Lysa and Huang Jianli, The Scripting of a National History: Singapore and Its Past (Singapore: NUS Press, 2008), 90. (Call no. RSING 959.5705 HON-[HIS])
13. “Barisan’s Chia Held in Security Round-Up,” Straits Times, 30 October 1966, 2. (From NewspaperSG)
14. “Chia Thye Poh a Free Man,” Straits Times, 27 November 1998, 2 (From NewspaperSG); B. Porter, “Singapore’s Gentle Revolutionary,” South China Morning Post, 30 November 1998.
15. Lydia Lim and Li Xueying, “ISA Arrests: The Legacy of 1987,” Straits Times, 7 July 2007, 68. (From NewspaperSG)
16. “Two Main Fronts in Conspiracy,” Straits Times, 27 May 1987, 14; Alan John, “Govt Detains Six More,” Straits Times, 21 June 1987, 1; Janice Heng, “Remembering the Marxist Conspiracy,” Straits Times, 3 June 2012, 18. Retrieved from NewspaperSG.
17. Ministry of Home Affairs, Singapore, Singapore Safe For All, 23.
18. “Francis Seow Detained under the ISA,” Straits Times, 7 May 1988, 1; “Francis Seow away on Short Holiday, Says Son,” Straits Times, 19 July 1988, 15; Martin Soong, “Lawyer Francis Seow Arrested under Internal Security Act,” Business Times, 7 May 1988, 18. (From NewspaperSG)
19. Lai Yew Kong, Chua Chin Chye and Philip Ganguly, “How Shankar the Trader Got Caught in the Jaws of the Tigers,” Straits Times, 17 May 1985, 12; “10 Leave S’pore after ISD Probe,” Straits Times, 28 June 1985, 12. (From NewspaperSG)
20. Ministry of Home Affairs, Singapore, White Paper: The Jemaah Islamiyah Arrests and the Threat of Terrorism (Singapore: Ministry of Home Affairs, 2003), 1–2.
21. Ministry of Home Affairs, Singapore, Jemaah Islamiyah Arrests and the Threat of Terrorism, 26–31.
22. “ISA Is Needed Now More Than Ever.”
23. “Militant Leader in Singapore’s Custody after Deportation by Indonesia,” Associated Press Newswires, 6 February 2006 (From Factiva via NLB’s eResources website); “Confluence of Factors Made Escape Possible,” Straits Times, 22 April 2008, 5 (From NewspaperSG); Nur Irfani Saripi, “Mas Selamat Kastari Arrested,” International Centre for Political Violence and Terrorism Research, 14 May 2009; website; Hetty Musfirah, “Mas Selamat Repatriated, Detained under Singapore’s ISA,” Channel NewsAsia, 24 September 2010. (From Factiva via NLB’s eResources website)
24. Jeremy Au Yong, “National Serviceman Detained under ISA,” Straits Times, 7 July 2010, 1; M. Nirmala, “Cracking Cyber-Terrorism Codes,” Straits Times, 6 December 2013, 39; Xue Jianyue, “Self-Radicalised S’porean Detained under ISA,” Today, 13 September 2013, 1. (From NewspaperSG)
25. Toh Yong Chuan, “Two Top JI Members Detained under ISA,” Straits Times, 12 October 2012, 1. (From NewspaperSG)
26. Wahyudi Soeriaatmadja, “Mas Selamat’s Son Deported to Singapore after Arrest,” Straits Times, 5 November 2013, 1. (From NewspaperSG); Lim Yan Liang, “Son of Mas Selamat Placed on 2-Year-Detention Order under the ISA,” Straits Times, 9 January 2014. (From Factiva via NLB’s eResources website)
27. Jeremy Au Yong and Kor Kian Beng, “Opposition Figures Air Key Issues at Dialogue,” Straits Times, 17 December 2010, 12; Tessa Wong, “Heated Words over ISA at Presidential Forum,” Straits Times, 20 August 2011, 6. (From NewspaperSG)
28. Li Xueying and Zakir Hussain, “Govt: ISA Still Crucial for Security in S’pore,” Straits Times, 17 September 2011, 1 (From NewspaperSG); Asian Human Rights Commission, “Singapore: The Singaporean Government Should Repeal the ISA,” press release, 4 October 2011; “Think Centre Renews Call to Abolish ISA,” Think Centre, 16 September 2011.
29. Asian Human Rights Commission, “Singaporean Government Should Repeal the ISA”; Lim and Li, “ISA Arrests.”
30. Rachel Chang, “Former Detainees Call for ISA’s Abolition,” Straits Times, 20 September 2011, 3 (From NewspaperSG); Chew, “Human Rights in Singapore,” 943; “Nine Ex-Detainees Say They Had Been Ill-Treated,” Business Times, 19 April 1988, 3. (From NewspaperSG)
31. “ISA Is Needed Now More Than Ever”; Workers’ Party, “Workers’ Party Position on the Internal Security Act,” press release, 16 September 2011; Elgin Toh, “DPM Teo: Terrorism Act Lacks Pre-Emptive Powers of ISA,” Straits Times, 20 October 2011, 1. (From NewspaperSG)
32. “ISA Is Needed Now More Than Ever”; Toh, “Terrorism Act Lacks Pre-Emptive Powers.” 
33. Toh, “Terrorism Act Lacks Pre-Emptive Powers.”
34. Ministry of Home Affairs, Singapore, Singapore Safe For All, 16, 23–25, 28.

Further resources
Abolish ISA? Maybe One Day. Give Foreign Papers a Free Hand? Never,” Straits Times, 19 November 1989, 22. (From NewspaperSG)

Carl A. Trocki, “David Marshall and the Struggle for Civil Rights in Singapore,” in Paths Not Taken: Political Pluralism in Post-War Singapore, ed. Michael D. Barr and Carl A. Trocki (Singapore: NUS Press, 2008), 116–30. (Call no. RSING 959.5705 PAT-[HIS])

Chan Sek Keong, “A Judicial View of Preventive Detention,” Channel NewsAsia, 21 February 2012. (From Factiva via NLB’s eResources website) 
Cheryl Crane, Mark Gillen and Ted L. McDorman, “Parliamentary Supremacy in Canada, Malaysia and Singapore,” in Asia-Pacific Legal Development, ed. Gerry Ferguson (Vancouver, B.C.: UBC Press, 1998), 155–217. (From ProQuest EBook Central via NLB’s eResources website) 

Clarissa Oon, “The Leftist Hole in History Books,” Straits Times, 17 June 2012, 42. (From NewspaperSG)

Kumar Ramakrishna, “Ensure S'pore's ISA Evolves with the Times,” Straits Times, 20 September 2011, 21. (From NewspaperSG)

Li-ann Thio and Kevin Y.L. Tan, eds., Evolution of a Revolution: 40 Years of the Singapore Constitution (NY: Routledge-Cavendish, 2009). (Call no. RSING 342.5957029 EVO)

Should Detainees Face an Open Trial?Straits Times, 26 January 2002, 15. (From NewspaperSG)

Teo Soh Lung, Beyond the Blue Gate: Recollections of a Political Prisoner (Singapore: Function 8, 2011). (Call no. RSING 365.45092 TEO)

The information in this article is valid as of 9 October 2014 and correct as far as we are able to ascertain from our sources. It is not intended to be an exhaustive or complete history of the subject. Please contact the Library for further reading materials on the topic.





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