My boyfriend's best friend treats him like crap

I never say anything to my boyfriend about his best friend because I feel like it's not my place, but this guy is the most manipulative piece of crap ever. He is treats my boyfriend badly and he's always doing dumb shit and having my boyfriend cover for him. My boyfriend had lied to the police for him. This is all out of guilt. 8 years ago when they were both 18 my boyfriend was drunk and was being dumb and accidentally got his friend hurt and fucked up his eye really bad. He had to have surgery on it and haven't been able to see very good out of that eye since. My boyfriend stays in friend and covers for him and let's him treat him badly because he feels bad about hurting him so long ago. When he wanted my boyfriend to lie to the police he started saying how he won't be able to get proper treatment for his eye in jail and if he doesn't he could lose it and some other manipulative bull crap. Me and my boyfriend have been together 2 years. Do you think I'm in my right to voice my opinion about this guy and if so how?