Support for a reset to the national inquiry into missing and murdered Indigenous women and girls is growing, according to grassroots groups.

More than 180 family members and 80 supporters have now signed an open letter asking Prime Minister Justin Trudeau to reset and reorganize the inquiry.

Last week, the inquiry named a new executive director, former Assembly of First Nations adviser Debbie Reid, but lost two more staff members: Susan Vella, the commission's lead lawyer, and Aimeé Craft, its director of research.

Those calling for a reset say the commission got off on the wrong foot by not including families and communities affected by MMIWG in the planning process. Instead, the letter says the inquiry "built its processes from a top-down colonial model that perpetuates institutionalized racism."

The letter says far too much damage has been done for the commission to rebuild trust with families and communities at this stage. It asks for a "hard reset" that would preserve information collected to date but restructure and rebuild the inquiry with Indigenous families and communities at its centre.

"Frankly, there just isn't the faith in the existing commissioners to do that because they've been asked throughout the entire year to find ways to make this happen and have repeatedly disregarded what families have said to this need for them to be included," said Julie Kaye, a sociology researcher at the University of Saskatchewan and a member of the coalition.

In July, the Assembly of First Nations passed a resolution at its annual meeting in Regina calling on the organization's leadership to demand changes at the inquiry. A resolution calling for the commissioners to resign did not pass.

At the time, Indigenous Affairs Minister Carolyn Bennett said that the commission was responding to calls for a reset by improving its healing support for families and communication with them.

Last month, the commissioners in charge of the inquiry asked the federal government for a two-year extension to carry out their work, citing the resignations, logistical issues and a lack of resources as challenges.