The lawyer later says, that they're only interested in solving Charlie's murder. All Mary needs to do, is say 'I was with Logan at the time of the murder'. He confirms that and she walks. Why wouldn't she do that? And why didn't the police also arrest the MC, who has no alibi, and just as big of a motive for disliking Charlie? And he has an equally compelling motive for hating Mike?
And when Mary is released from prison, she says Logan was there when she was arrested. So why was she kept there for so long, when he can provide her with a cast iron alibi? And even after she's released, the lawyer claims she's still the main suspect. How could that be the case, when one of the police detectives, knows it's impossible for her to have committed that crime, because she was with him when it happened?