She will be first up at 10am and is expected to be cross examined in the box for two days.
She is an important witness since she was the first senior Conservative councillor to blow the whistle on the alleged gerrymandering.
She has been called as a witness by Dame Shirley Porter and Tory MP Barry Legg.
This will be the first time during this whole five-year saga that Dame Shirley will have given a detailed defence in public to the allegations. It is expected to take four to five days.