It depends upon who is recording your telephone conversation and for what purpose. If for example, the Indian government or state governments and income tax departments are recording your conversation as a evidence to produce in a court then it is allowed by law. But if any individual is recording your voice without your concern and sharing it with others or blackmailing you is illegal.
Section . 5(2) of Indian Telegraphs Act 1885, the Central and State governments can tap your phones. If police or any government departments need to watch you secretly in order to safeguard the public safety then they can tap your conversations. During the time of emergency or danger to national security like terrorist movements or fear of terror attack the government can record any citizen's phone to gather information.
Though tax offences were covered under the reason for recording of personal phones, the same was withdrawn following the supreme court order in 1999.
As per the Indian Telegraph rules , no one can use the telephone for other purpose than for calling other people or receiving calls from others.
If you think that your phone is tapped then you may call Human Rights Commission as your right of privacy is intruded. You can file a complaint against a person, whom you are thinking is recording your telephone.
If any police department person is recorded your voices and showed it to some other persons who don't have the right to see it, then you may sue that police official.
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