National MP Paul Quinn, from Ngati Awa, admits his private member's bill aimed at taking the vote away from people in prison will disproportionately affect Maori.
Currently only prisoners serving a three-year sentence or longer are barred from voting.
Mr Quinn's Electoral Disqualification of Convicted Prisoners Bill would remove the right to vote from all inmates on election day.
He told Waatea News the fact that one in two males and almost two-thirds of female prisoners are Maori didn't affect his thinking.
Before offenders get their first prison sentence, Mr Quinn says, statistics show 80% will have been convicted at least 10 times.
The bill is before the Law and Order Select Committee.