A Papua New Guinea MP Peter Yama has applied to the Waigani National Court to recognise him as the governor of Madang.
Last week the incumbent, James Yali, was convicted of raping a teenage girl in 2004.
He is due to be sentenced shortly and is likely to receive a prison term.
The National newspaper reports Mr Yama's lawyer, Ben Lomai, saying Mr Yali had disgraced the governor's office and brought shame to the people of Madang.
But James Yali's lawyer, Pius Kingal, argues that until his client is sentenced, he remains the governor of Madang.
The court is expected to deliver its ruling on Wednesday.