This other article provides further details.
https://www.cbc.ca/news/canada/montreal/mk-ultra-class-action-lawsuit-u-s-immunity-in-canada-1.6985475
Basically the 3 judged decided that the law that was passed in the 1983 couldn't be retroactively applied.
However the plaintiffs say it can since it was retroactively applied in other cases.
This other article provides further details.
https://www.cbc.ca/news/canada/montreal/mk-ultra-class-action-lawsuit-u-s-immunity-in-canada-1.6985475
Basically the 3 judged decided that the law that was passed in the 1983 couldn't be retroactively applied.
However the plaintiffs say it can since it was retroactively applied in other cases.