Ian Cusson
Two years ago when Harry Somers’ Louis Riel was revived in Toronto, Ottawa and Quebec there was considerable debate about the appropriation of a traditional Nsga’a morning song; the Kuyas. Basically in the culture the song comes from transmission and use of songs are regulated by the traditional owners. This particular music had been used to set the text of a lullabye that Riel’s wife sings to their child, originally without attribution. In 2017 the decision was made to use it again though not without consultation, debate and acknowledgement. See my comments about the issue on opening night here.
It’s fair to say that I don’t think anybody thought the status quo was really acceptable and a great deal of discussion has gone on leading to an announcement this morning that the music will be replaced in the opera by new music composed by Ian Cusson, who is of Métis and French-Canadian descent. The whole story; whats, whys and wherefores, is contained in the linked COC press release. It’s the right thing to do and it’s the right composer.
operaramblings 
How would Harry Somers, the composer of the original opera Louis Riel have reacted to inserting a new composition into his creation?
As I knew him, in 1968, not well at all!
I strongly disagree with inserting a new composition into the original opera Louis Riel. IMHO, it is reckless and incorrigible.
I write this with all respect to the Nisga’a who created this song; and in respect of and for the indigenous members of my immediate family.
I have to disagree. A wrong needs to be righted. Somers isn’t alive to make the decision on how to do it so his estate, surely the appropriate proxy, has acted. This seems a reasonable way of proceeding. The alternative is to accept that there can never be resolution around something done by someone who has died which I think would be intolerable.