The 12-member commission is expected to release a report by Dec. 15, The Daily Herald reported.
"Today we begin a new effort to understand" the landslide, Gov. Jay Inslee said. "Through this effort we will act on what we learn and support the healing process of this community."
The commission will be led by Kathy Lombardo, who has worked for the Bill & Melinda Gates Foundation and CH2M Hill.
Members were appointed by the governor and Snohomish County Executive John Lovick.
Earlier this week, a team of seven independent researchers released a report blaming heavy rain and previous landslides as well as multiple other factors for causing the deadliest landslide in U.S. history.
The scientists said there have been 15 large mapped landslides in the Stillaguamish River valley over about 6,000 years. The slides are estimated to happen every 400 to 1,500 years.
The Oso mudslide four months ago occurred in two major stages minutes apart, according to the scientists.
Members of the new commission include David Montgomery, director of geomorphology at the University of Washington and an expert on how landscapes are shaped. He will be joined by experts in development, planning, public safety and emergency management.
The March 22 landslide killed 43 people and caused millions of dollars in damage to homes and Highway 530. It sent 10 million cubic yards of dirt and debris a mile from the top of a 600-foot-high hillside.