What is expected from the citizen of India with respect to the singing of our national anthem- ‘jan gana mana’. National anthem reflects the people of the country, their culture, their struggles and their stories through time. It represents our country and who and what we stand for It is a patriotic song that binds people together and is officially recognised by the government. Whenever this song is played people feel they are at home, stand in unity and sing together with utmost patriotism forgetting every barrier among us. It gives a sense of pride, glory, respect and oneness, that is the reason it is encouraged to sing the national anthem in schools, colleges, gatherings, etc .

In this case, students from Kerela were expelled from their school for not singing the national anthem. They basically refused to sing because they followed the religious faith of Jehovah's witnesses according to which (allegedly) it was against their religious beliefs. The case went to Kerela High Court and was dismissed on the grounds that the anthem did not contain any words that were against their faith so their expulsion is valid. The father of the students then filed a special leave petition in Supreme Court of India and the apex court found that student's Right to freedom of expression that is Article 19 and Right to religion that is Article 25 of Indian Constitution was violated on expulsion from the school, as even though they did not sing they were standing which clearly represents their respect towards the national anthem. Intrestingly,  in another case in Kerela, the police charged a youth naming Salman for sedition and 6 other people for not standing when the national anthem was being played in the cinema hall. Subsequently, the High Court observed that Salman did not commit any offence amounting to a threat and security of the nation by his actions and hence was granted bail. As per the law, it is not mandatory to sing. In the past also there has been no judgements or directive by any legal authority which makes it mandatory to stand and sing. So, it boils down to one's own patriotic feeling and respect for the nation. 

so, in this case, Supreme Court held that the three students were not guilty of disrespect to the national anthem just because they refused to sing it. Moreover, they were standing in respect while others were singing. The reasoning behind this was that there is no legal provision that obligates anybody to stand and sing the national anthem, expulsion of students were violation of their fundamental rights that is right to freedom of expression, right to religion and right to remain silent and hence the students were permitted to study in the school without any hindrance.