This, from Jacqueline Tempera in the Providence Journal, seems related to the decriminalization of child prostitution in California:

Amnesty International’s policy on sex workers, which was published in May after a vote by chapters internationally, calls for “the decriminalization of all aspects of adult consensual sex work due to the foreseeable barriers that criminalization creates to the realization of the human rights of sex workers.”

[Rhode Islander Marcia] Lieberman, and most of the members of the 10-person chapter she coordinated, disagreed with this, she said. They felt the research into the policy was scant and that it would embolden “pimps and johns” who were exploiting “mostly young women and girls.”

“We believe there should be help for people in sex work,” Lieberman explained in an interview. “But we did not believe it should be legal for customers to buy sex.”

So, Amnesty International excommunicated her.  The organization is free to have its policies about internal agreement when it comes to its far-left, radical progressivism, but consider the issue that this is about.  There may be more to the story than presented, of course, but this hardly seems like an issue so fundamental to the organization that no prudential disagreement can be tolerated.

One certainly gets the impression that there’s an ideological agenda at work behind the scenes across the progressive movement.