Mistakes, we all make them. However, it's not everyday that your mistake could be the death of someone at the hands of the needle. Angela, the woman who loved Ghost more than she should have was hellbent on putting him in jail for the death of her ex-boyfriend Greg, that she did not dot all of her i's and cross all of her t's. However at the end of Epsiode four in season 4, Angela knew she screwed up when she saw the footage of the last time Ghost was in his office and there was NO GUN!
After Proctor was removed from the case, he and his drunk kind paid Angela a visit where he assured to her Ghost's innocence. While she did not believe him, she had to check it for herself, why? Cause she is a perfectionist (in the words of Courtney Kemp). Now what? Angela has to find a way to fix this. More than likely this will involve her turning on one of her team members. Because now she knows that someone planted the gun. And if Tommy, Tasha and Keisha didn't hate her before they sure will now. Now Ghost is closer to coming home but considering the kids titution is behind, Tariq is running with Kanan, and Tasha can't trust him, he is on his way back to a home of hell.