What a missing and murdered indigenous women inquiry could learn from an inquest in Thunder Bay, Ont.

A coroner's inquest into the deaths of seven First Nations students in Thunder Bay, Ont. is providing a glimpse into what needs to be done as part of a national public inquiry into missing and murdered indigenous women and girls, Ontario chiefs say.

The federal government will announce on Tuesday some of the details of the much-anticipated inquiry.

Meanwhile, the Thunder Bay inquest is into the third of six months of evidence examining the deaths of youth from remote First Nations who died under mysterious circumstances while attending attending high school in the city.

• Missing and murdered indigenous women inquiry details coming Tuesday
• CBC News Investigation: Missing and Murdered
• IN DEPTH: First Nations student deaths inquest

A national inquiry "has to be family focussed, families need to be able to participate and have a say in terms of how this is rolled out and how they can participate," said Nishnawbe Aski Nation Grand Chief Alvin Fiddler.

Fiddler, a key proponent of the inquest in Thunder Bay, said his organization began working with families two years before the proceedings began and will continue to provide mental health supports after it is over.

"I think it's important that we have those pieces in place so that the families feel supported and feel comfortable enough to participate in the process," he said.

In November, Ontario Regional Chief Isadore Day called for community-wide supports for the "wounds being opened" at the inquest, expressing concern that government-run proceedings might not be "equipped to ensure people are safe" after hearing devastating details about the students' deaths.

A national inquiry into missing and murdered indigenous women and girls has the potential to be traumatizing for families who have lost someone, Day said.

"We are dealing with a major issue with regard to the inquest into the seven deaths, can you imagine us going through the national inquiry process and what challenges that might pose? It's a little scary," he said.

A lack of support for family members at the time of death is a key theme emerging at the inquest that will likely emerge in stories of missing and murdered indigenous women, Fiddler said.

"Families have said that they didn't feel supported by those in authority, they could have taken these cases more seriously," he said. "Whether it's the Thunder Bay police, the Ontario Provincial Police or the coroner's office, nobody even called them." 

Fiddler said racism experienced by the students away from home is another common theme at the inquest that he expects will also come up in a national inquiry.

Families of missing and murdered indigenous women and girls have already expressed concern about a national inquiry becoming too political, Day said.

Status of Women Minister Patty Hajdu said Monday, the Liberals will try to keep politics out of the process.

"We want to make sure that this isn't something that is oppositional in any way and that it's seen as something that is beneficial to the families and to the communities," Hajdu said.