Indian PM Modi is considered by some to be a divisive figure, promoting Hindutva rather aggressively.
A familiar accusation, often repeated by foreigners, is that, as Chief Minister of the state at the time, he "was involved in" / "did not stop" the 2002 Gujarat Riots in which 2000 people, mostly Muslims, died. This was considered a serious enough charge that many Western governments wanted to deny him visas in the aftermath.
On the other hand, his defenders will say that he was cleared of wrongdoing by the Supreme Court of India. And, yes, sometimes riots do result in considerable losses of life and property before they are stopped, without nefarious intent by the government. Yet, the wikipedia entry shows that was also some concern about the impartiality of the ruling.
What were the key facts supporting either his guilt or innocence? Maybe things like police deployment response times and orders, public speeches to call for an end to violence, etc...
p.s. It can be said that Modi doesn't have the most friendly attitude towards Muslims in India. Please don't base your answers primarily on that point, this question is about the 2002 riots, not Modi's tolerance or not since he is PM of India.