Toews introduced a "three strikes" bill to the House of Commons in October 2006, stipulating that persons found guilty of three sexual or violent crimes will be automatically categorized as dangerous offenders unless they can convince a judge otherwise. Persons labeled as dangerous offenders under Canadian law may be kept in prison indefinitely. Critics argued that the proposed law was too broad in its scope, and included vaguely defined categories in its list of serious offenses. Civil libertarian groups also argued that the bill threatened the constitutional principle of accused persons being presumed innocent until proven guilty, and suggested that it may not withstand a court challenge.