Mr. Plant is, as noted, a lawyer and a former Attorney-General (he was NOT a good Attorney-General, but that's beside the point). He should have the applicable laws and Rules memorized. The requirement that the Speaker must be a MLA is found in s. 37 of the BC Constitution Act, which despite its name is ordinary legislation that can be amended in the ordinary fashion.

The new government can solve the Speaker problem very simply by amending s. 37 to remove the requirement for the Speaker to be a MLA. A non-member Speaker, who would be an officer of the Legislature, would give the NDP/Green alliance a one vote majority.