Singapore is a parliamentary republic where the People's Action Party (PAP), in power since 1959, overwhelmingly dominated the political scene. The 2011 general and presidential elections were viewed as open and free, with the major opposition party winning a record six seats in Parliament. The by-election held during the year was viewed as open and free, with the major opposition party winning the contested seat. Authorities maintained effective control over the security forces. Security forces did not commit human rights abuses. The government has broad powers to limit citizens' rights. The government could and did censor the media (from television shows to websites) if it determined that the content would undermine social harmony or criticized the government. The Internal Security Act (ISA) permits preventive detention without warrant, filing of charges, or normal judicial review; in recent years the government has used it against alleged terrorists and not against persons in the political opposition. The following human rights problems were reported: Caning is an allowable punishment for some crimes; restrictions existed on free speech and assembly; government intimidation led to self-censorship by journalists; some limited restriction of freedom of religion; and some restrictions on labor rights. The government prosecuted officials who committed human rights abuses, although there were no instances of such prosecutions reported during the year.