An election law expert says it could work in Labour's favour for it to not win many Māori electorate seats. 

Te Tai Tokerau MP Mariameno Kapa Kingi has announced she is splitting from Te Pāti Māori and forming her own party. 

Otago University Law Professor Andrew Geddis says there could be overhang seats if either party wins electorates with a relatively small party vote.  

He says told Ryan Bridge it would then increase the number of MPs needed for a majority. 

Geddis says winning the Māori electorates could mean Labour falls short of being able to form a government.