While granting reprieve to five activists who were arrested yesterday under an anti-terror law on charges of Maoist activities, the Supreme Court today said: "Dissent is the safety valve of democracy". The court said poet and Maoist ideologue Varavara Rao and activists Sudha Bharadwaj, Arun Fereira, Gautam Navlakha and Vernon Gonsalves, will be under house arrest till the next hearing on September 6.