The Electoral Commission is looking to see whether discrepancies at three polling places are isolated or more widespread. 

It's launched a check of all voting place results after our newsroom picked up errors at two polling places at Port Waikato, and one polling place in Ilam. 

More than 500 votes at one polling place were wrongly assigned to the Leighton Baker Party, rather than National. 

Political commentator and former United Future Leader Peter Dunne told Kate Hawkesby that it's one of several issues that will need to be addressed when the electoral process is reviewed at select committee. 

He says the commission also needs to answer questions about the time it took to count the votes, and whether there were enough polling places on election day. 

LISTEN ABOVE 

• 'Full check': Electoral Commission reviewing voting results after Herald identifies error