Art.21 of the Indian Constitution says that “No person shall be deprived of his life or personal liberty except according to procedure established by law.”
The expression ‘personal liberty’ includes ‘right to privacy’. A citizen has a right to safeguard his personal privacy. The act of telephone tapping affects right to privacy as well as right to freedom of speech and expression, both of which are Fundamental Rights under the Constitution. Hence it is clear that phone tapping is violative of Article 21.
Although the Central Government as well as the State Governments, both of them are provided with the right to intercept telephones under Section 5(2) of Indian Telegraphic Act, 1885. There are instances when an investigating authority/agency needs to record the phone conversations of the person who is under suspicion. Such authorities are required to seek acquiescence from the Home Ministry before moving forward with such an act. In the application to seek permission, particular reasons need to be mentioned. Additionally, the need for interception of telephone must be proved. Then only the ministry will consider the application and grant permission upon estimating the merits of the application for interception.
In the case of S. Pratap Singh v. State of Punjab, the Supreme Court permitted the recording of a intercepted telephonic conversation between the Chief Minister’s wife and a doctor to be divulged as evidence to substantiate the evidence of witnesses who had mentioned in his statement, that such a conversation had taken place.
Hence, to answer your question, it depends on the type of person X is and whether he/she has permission of tapping someone’s phone or not. In any possibility, it would mount to infringement of privacy.
Hope this answers your question.