'A', a police constable tortured a person under the order of his senior police officer. The person lost…

Obedience to a superior officer's order and threats to one's service are no defence to voluntarily causing grievous hurt, so the grounds that "torture was under the order of senior police officer" or that "torture was given because he was under the threat of losing service" fail. The only recognised excuse of duress under s.32 BNS (formerly s.94 IPC) requires a threat of instant death (and even then not for offences like murder), so the defence can rest only on the ground that "torture was given because there was imminent threat to death".