Are you talking about Addison? Doctors are required by law to report sexual assaults. While Addy did tell Sam about the rape, no one told Violet - she figured it out based on Charlotte's behavior and her own past experience. Plus, she isn't Charlotte's doctor, nor is Sheldon, so they aren't bound by confidentiality laws.
I think Pete did the right thing not lying to get his mother released from prison. She's obviously a manipulative person who had no remorse for murdering her husband or ruining her sons' childhood.
KaDee Strickland has just been hitting it out of the park with this storyline. I'm blown away by her performance. Charlotte has never been a warm person, so I'm glad they've been true to who the character is as she goes through this ordeal. While they all love Cooper (okay, maybe not Pete), I don't think they like Charlotte all that much, even if they do care about what happens to her. She's not a terribly likable person.
The final scenes with Cooper and Charlotte had me in tears. I love him.