The Vice President of India is an ex-officio Chairman of the Council of States or the Rajya Sabha. He is not formally elected as a Member of Parliament; so, he is not formally an elected member of the Rajya Sabha. Yet, he has a right of casting vote on the floor of the House in case of equality of votes on an issue. What is the reason for this?
Article 64 of the Constitution, as well as Article 89 of the Constitution, clearly and specifically lay down that the Vice President of India shall be the ex officio Chairman of the Council of States (Rajya Sabha). Thus, the Vice President of India is declared as the Chairman of the Rajya Sabha by the Constitution itself, even though he is not elected as a member of the Rajya Sabha.
Moreover, Article 100 of the Constitution specifically and clearly lays down that the Chairman (of the Rajya Sabha) shall have a casting vote in case of an equality of votes, though he shall not vote in the first instance.
The relevant extract from Article 100(1) of the Constitution is as under:
βThe Chairman or Speaker, or person acting as such, shall not vote in the first instance, but shall have and exercise a casting vote in the case of an equality of votes.β
Thus, the Constitution itself lays down that the Chairman (of the Rajya Sabha) shall not vote in the first instance, but in the case of an equality of votes on any question, the Chairman shall have a vote and exercise a casting vote.
In their own wisdom, the makers of the Constitution decided to have these provisions in the Constitution. Since the Vice President is made the Chairman of the Rajya Sabha (which means that he becomes a part of the Rajya Sabha), he has been given the right of a casting vote in case of equality of votes. In other situations, he does not have a right to vote.
Thus, the Vice President being the ex officio Chairman of the Rajya Sabha, has the casting vote in case of equality of votes on any question that is voted upon in that House.