An 11-member investigatory panel in the attorney-general's office had unanimously found them guilty of gross misconduct in April's inconclusive elections.

ECONOMIST: Prosecutors now want both the main parties scrapped

The tribunal members ruled in January that Mrs Hill's actions "amounted to gross misconduct" and upheld the school's "decision to summarily dismiss".

BBC: Carol Hill

"By utilizing the derivative action, CalSTRS is seeking to remedy the damages sustained by Wal-Mart as a result of alleged gross misconduct by Wal-Mart's executive officers and directors, " CalSTRS Chief Executive Officer Jack Ehnes said in a statement.

CNN: STORY HIGHLIGHTS