The process to remove someone from a circle is, on a process level, rather easy: it’s a proposal with clarifying questions, quick reactions and a consent round. The only difference to any other proposal is that the person asked to be removed does not have consent rights. That person can be included in the clarifying questions and in the quick reactions. If there are no objections, then that person loses circle membership.
For more information, check out our handbook Many Voices One Song sections 2.2.3, 6.5, and chapter 4