1967: The Unlawful Activities (Prevention) Act: Legislated to counter activities that questioned the nation's "territorial integrity"
1980: The National Security Act: It made preventive detention possible
1985: Terrorist and Disruptive Activities (Prevention) Act (TADA): Initially meant to act against Punjab extremists but was used extensively elsewhere too
2002: Prevention of Terrorist Activities Act (POTA): The NDA passed this act; repealed in 2004 by the UPA government