Section 297
Prohibition Of Opening Letters Or Tapping Telephone Conversation

(1) No person shall open a person's letter or tap or record a person’s
telephone conversation by using any mechanical device, without
permission of the competent authority or the concerned person.
(2) A person who commits, or causes to be committed, an
offence under sub-section (1) shall be liable to a sentence of
imprisonment for a term not exceeding two years or a fine not
exceeding twenty thousand rupees or both the sentences.