Factbox: Canada's anti-terror laws, and what might come next

(Reuters) - Canadian Prime Minister Stephen Harper pledged more powers for security forces on Thursday after a gunman killed a soldier on Wednesday and then raced through the country's Parliament building in Ottawa before being killed. Canada has introduced a series of legal changes since Sept 11, 2001 meant to prevent possible attacks, toughen penalties and make offenders easier to prosecute. ANTI-TERRORISM ACT Canada passed this legislation after the Sept 11, 2001 attacks. It brought in new powers and penalties designed, in part, to prevent attacks. It defined "terrorist activity", established an official list of "terrorist entities", and created several new criminal offenses, instructing someone to carry out an attack, for example. Two measures were temporary. The first allowed for preventive detention in some circumstances. The second allowed for investigative hearings in which a judge could compel someone with information about a possible attack to appear in court and answer questions. These provisions expired in 2007, but have since been reinstated. COMBATING TERRORISM ACT Introduced in Parliament in 2012, this law reinstated the investigative hearings as well as the preventive detention provision, which is called "recognizance with conditions", from the Anti-Terrorism Act. The act allows law enforcement agencies to bring suspects before a judge, who can impose conditions on them to prevent an attack. If they do not follow the conditions they can be jailed for up to 12 months. The same legislation, which became law in 2013, makes it illegal to leave, or attempt to leave, Canada with the intention of carrying out an attack, and increases penalties for some related offenses. NUCLEAR TERRORISM ACT This act, which also became law last year, creates four new criminal offenses and penalties related to nuclear attacks, including threatening or interfering with the operation of a nuclear facility. Transporting radioactive material with an intent to cause death or injury could draw a life sentence. PROPOSED CHANGES Public Safety Minister Stephen Blaney said last week the government is preparing to boost the powers of the country's spy agency, the Canadian Security Intelligence Service (CSIS). Blaney said the government is committed to addressing the threat posed by Canadian residents who become radicalized, and what he called the growing problem of extremist travelers. He said the changes would let CSIS track and investigate suspects when they travel abroad, leading to prosecutions, but specifics of the new legislation have not yet been released. The Globe and Mail newspaper reported that government officials were also discussing whether CSIS should be given explicit permission to use "threat-diminishment" tactics such as "aggressively interviewing" a parent or employer of a young suspect who has not been charged. On Thursday, Harper said laws and police powers must be strengthened "in the area of surveillance, detention and arrest". (Reporting by Allison Martell; Editing by Jeffrey Hodgson; and Peter Galloway)