I don't know much about laws. Can decisions made under common law be changed?
The current system isn't working. Many reserves are rife with sexual abuse, domestic abuse, drugs and alcohol abuse, child abuse, fraud, criminal behavior, and so on. Money get's thrown at reserves and intercepted by a few gate keepers who merit it out how they see fit, mostly with no transparency or accounting. Look at
Lytton BC. $290 million dollars in recovery funds and not a single house rebuilt yet. First Nation suffering is a self-perpetuating business. Maybe the solution is to just rework those 300 year old contracts from scratch.