A plan to count only citizens of voting age in determining the configuration of new electoral boundaries could be a violation of children's rights, Bob Pringle, Saskatchewan's Children's Advocate, says.

The province has launched a process to redraw the electoral map.

In addition to boosting the number of politicians to 61 from 58, the province wants the size of each constituency determined based on the population that is over 18.

But according to Pringle, that could violate the Charter of Rights.

"Section 3 of the charter is intended to ensure effective representation of the whole population, not just those over the age of 18 years," Pringle said Tuesday.

Pringle added the exclusion of minors may also run afoul of the Charter's equality provisions.

He said not counting people under 18 would affect communities with a large youth component.

"Leaving children, youth, out of the population count to calculate the boundaries will have a significant effect on the political representation of aboriginal people and new immigrants due to their much younger demographics," Pringle said.

Saskatchewan's Justice Minister, Don Morgan, said Tuesday he is aware of Pringle's view and he disagrees.

He said it is fair to count only people of voting age.

With files from CBC's Kathy Fitzpatrick and Stefani Langenegger