Note first of all that it could refer syntactically to the Nebraska Supreme Court or to the chair, but world knowledge rules out the possibility of a neuter-gendered chair manifesting a mental attitude.  Note as well that if it is replaced by he, then the chair  is reinterpreted as a person and becomes the referent of the pronoun; at the same time, threw out is then reconstrued as a metaphor meaning removed from office (with an implication of ruthlessness).