The opposition Cook Islands Democratic Party says it is appalled that the government is planning to appoint Toka Hagai as a seventh cabinet minister.
Mr Hagai stood for the governing Cook Islands Party in Rakahanga during the June elections but lost the seat after a court found he treated voters to free food and drinks at his rally.
The decision saw the Democratic Party's Tina Browne declared the successful candidate.
Ms Browne said if Mr Hagai is sworn in as a cabinet minister, it would make a complete mockery of the country's judicial system and decisions made in the court of appeal.
She said it would demonstrate that the current government will stoop to anything to remain in power.
Ms Browne said the public did not deserve to be saddled with the cost of a seventh minister when the chosen person did not bring a specialised set of skills to national decision making.
She added that to reward Mr Hagai with ministership after being found guilty of electoral treating goes against good governance, accountability and democracy.
Iaveta Short who was a member of the former Political Reform Commission (PRC) and co-authored a report on reforming the country's political system says if Toka Hagai is appointed it would "clearly undermine the decision of the court of appeal".
Mr Short explained the PRC had recommended that a seventh minister could be appointed from outside of parliament but this was based on the principle that such a person would bring excellent skills in finances and or the law.