The premier is set to testify for a second time at the hearings into the gas plant cancellations.
Kathleen Wynne will answer questions from an all-party committee Tuesday afternoon. The last time she appeared was in April.
The NDP called on the Premier to testify one more time, after the Auditor General's report on the Oakville gas plant cancellation. It contained new information about the government trying to avoid a law suit from the developer in the Oakville cancellation.
At the time, NDP House Leader Gilles Bisson underlined the public needs to know why the province chose the most costly route to relocate the Oakville gas plant.
In the spring, Wynne underlined she wasn't involved in either cancellation, despite being Liberal campaign co-chair in the 2011 provincial election. She was also a member of cabinet at the time of both cancellations.
Wynne did admit she signed a cabinet document to allow negotiations to proceed on the Oakville plant, but said that was eight months after the project was cancelled in 2010.
The Mississauga and Oakville gas plant cancellations will cost taxpayers at least $1.1 billion.