So my story tackles a lot of issues and one of the issues is Black Lives Matter. My main character does not like them he views them as racist and offensive and gets very in your face over it. One of the reasons is that a friend of his(who is black) in the story had his business and livelihood destroyed(a child killed) durring a BLM riot and the character gets really pissed off when ever he sees people glorify Black Lives Matter. Basically the main character views them at best as misguided and at worst he views them as low life thugs and does not like the group at all. The group is not portrayed in a positive light at all.
Your story is fiction, right? Creating a fictional incident to condemn a real-world group seems like an extraordinarily bad idea. Yes, it's offensive. I also wouldn't be surprised if it were actionable. Your character can dislike anybody he wants, but when you make up fictional sins committed by real people or groups...that looks like very shaky legal territory.
Not fictional sins more like inspired by real life events. BLM have done terrible things if not many have done terrible things in the name of BLM however no action or response is made. http://conservative-headlines.com/2016/08/mob-chanting-black-lives-matter-viciously-assaults-whites-in-akron-oh/ However I will scrap the idea.
Especially with political topics, nuance is needed. Showcasing the violent side of a movement like BLM is a valid story, but painting such a movement as just that, that's creating a caricature. A good critical look at such a topic explores the rational and the ideas. Focusing in on of the bad sides of the whole is offensive to the depth such issues have.
Create a fictional movement of your own for your character to hate. Basing this off the BLM movement and (even if it's through your character) tarring all the members as evil, violent police/white-haters is generally...well...a good idea if you want to get your ass thrown in the metaphorical boiling pot. Now, on the flip side... this is fiction and I'm assuming your main character will go through an arc where he slowly forgives the movement as a whole and comes to see that not all of them seek violence and destruction. (Maybe he sees a totally hot chick whose part of the BLM and begins to fall in love with her? OK, clichéd but still!) So... here's my thought: what if you also showed the good side of BLM? Show all the aspects of the movement both the good and the bad via different POVs? Maybe one of the POVs can be someone who is part of the BLM and is actually trying to make a change sans the violence part? I don't want to come off as saying, “No, you're not allowed to write this!” because in my mind, we can write whatever we want. All I'm saying is that if you do this, expect to have readers who will think you're using the book to condemn BLM as a violent group who wants to kill police officers and white people, and react accordingly. Every action has a consequence.
Add another voice saying this sounds like a bad idea. If it were just your character with the attitude that would be one thing (still problematic, not as much) but it sounds like you share the attitude, in which case you're essentially using fiction as an excuse for a polemic. I'm not saying it can't be done... look at the conservative talk show hosts and their agenda-fuelled drivel masquerading as fiction. But they have built-in platforms for selling their books; I assume you don't.
There is a lot to question here, my first point is that BLM is not 'an issue'. If your story is a vehicle for attacking any group then it is, without doubt, a bad idea. If, however, the main thrust of the story is about something else, and the character you mention is developed throughout, then maybe it could work.
If we were visiting in person, @Tenderiser and I could join in and say "Poetry is a bad idea" all together. (Ah, the classics never get old). But I'd be being facetious, and I expect she would be, too. Although you can never tell with @Tenderiser... ETA: And the cross-posting seems to establish that, as usual, @Tenderiser is out in the grass on this one.
That is treading very dangerous waters! Unless you are re-telling a REAL event and advertising it as "based on a true story" then I think you need to stay well away from using any real groups. The story idea itself is good, but if you want to go ahead with it then you need to make up a totally fictional group.
As for BLM, stay away from it. Unless you're deliberately trying to court controversy, avoid any social movements whatsoever, especially those that are currently around.
I don't, but I'm not black (or a person of colour, if that's a less offensive way to say it ATM). I see what you're getting at, the irony of a BLM protest destroying that which it was meant to protect. But... Unless you yourself are a POC, I'd leave this subject alone. And I'm assuming you aren't since you're asking on here about how appropriate it is to write on this topic. Since you are not a POC, you will not win. No matter what you write, someone will be offended. Some of the things you're likely to hear are: it's not your story to tell, you forgot <such-n-such> which is a big part of the issue (whether you did or not), just another white liberal trying to prove how open-minded he/she is, you should have looked at it from *this* POV, not the one you took, or you just contrived the situation to make POC look bad. Of course, if you are a POC, have at it. It's your story and even if it isn't, you're close enough to the nucleus to have a pretty fair idea of what needs to be said.
I fervently disagree that one needs to be a person of colour to write about this subject, which is what Sack a doo is suggesting. On the other hand, you do need to be qualified, IE knowledgeable on the subject, even if you satirise it.
Here's another thing to consider: If someone decides to sue you for defamation, do you have the money to fight it in court? Rockstar gets crap constantly for all the controversy they stir in their Grand Theft Auto series and the only reason they can get away with it is because they're one of the bigger, richest videogame companies out there and can take it. A lowly writer like you and me? As John Marston, lead of Rockstar's Red Dead Redemption, once said, "If you find yourself digging a hole, first thing to do is stop digging!" And, I don't mean to be talking smack against my fellow countrymen here but...since this is such a sensitive, delicate, hot-buttoned issue right now in the United States, unless you're currently not in the United States/or not an American, and I will assume also that you're white, you'd do well to steer clear of this issue. Granted, I doubt a white Austrian all snug and comfortable in his/her lovely home would do much better. Buuuut that's my cynical side talking.
Interesting that you should mention GTA. I bought GTA V for PC when it was released, not only to see how it plays but also to see how offensive it was supposed to be, which wasn't very much actually. Today's society is so offense sensitive that it's getting difficult to know who not to offend.