We critically examine the definition of ‘terrorism’ in the Anti-Terrorism Act 1997 of Pakistan and as it is interpreted by the Supreme Court of Pakistan under the principle of legality in criminal and human rights law standards. 1  We conclude that the definition of terrorism under the Anti-Terrorism Act does not pass the test of the principle of legality and the jurisprudence of the Supreme Court of Pakistan is inconsistent confounding the situation further. We recommend that Pakistan, following the principle of legality and human rights standards, amend the current definition of terrorism as an overbroad definition could be misused and abused leading to human rights violations.