For my detailed study next year I'm thinking about doing the "Nanjing Massacre", obviously it carries strong historically and emotionally ties - so I'm wondering if this would be inappropriate? I've tried to avoid this topic but this topic holds the greatest interest for me personally.
Thanks.
Personally, I don't believe it's a good idea.
The Nanjing Massacre is an event that is imbued with a strong emotional connotation for most Chinese people, and so it would be very difficult to base an impartial discussion on it without sounding somewhat disrespectful. Most conventional detailed study formats require discussion of the topic's positive and negative aspects; while this can be done with some other historical events, how are you going to discuss the 'benefits' of such an atrocity? Not to mention it also treads into the sensitive discussion of China-Japan politics/relations, which is always best steered clear of.
Optimally, detailed study topics should be ones that can be discussed without being emotionally stirring. You want to
interest your examiners, but not persuade or emotionally influence them. There is no way of knowing who your examiners are going to be and what kind of response they may have towards the topic - accidentally offending or upsetting them is the last thing you want to do. With a culturally sensitive topic such as the Nanjing Massacre, a misplaced adjective in your script might be enough to label you as inconsiderate/rude.
TL;DR I think it would be best if you chose another topic. If you really, REALLY have a strong interest in this and have absolutely nothing else, I would suggest discussing it with your teacher this/next year to see what they think and if they can help.
This is just my two cents but I hope it helps. Good luck!