Under treaty rights, Indigenous people who acquire a licence can harvest an unlimited number of walleye with a net. But under Alberta government's rules, at that time, all walleye caught for sport had to be released.

Cunningham, who had a licence, said he was fishing with a rod for food. The conservation officer told him that was considered sportfishing.

Cunningham handed over his catch and then tried to explain to his eight-year-old son why the conservation officer took their fish.

"He (conservation officer) didn't understand what treaty rights are," Cunningham, who has a master of laws specializing in Aboriginal and treaty rights, explained to his son. "We have a treaty right to catch fish but he didn't understand what it means, so now I have to go to court and talk to the judge and explain what a treaty right is and why we have a treaty right to keep these fish."