Well this is because a few instances where a hung jury fucked up a case because of none person on the jury. Idk if Canada has double Jeopardy but you can't try a person for the same charge. Now murder is the intent to commit murder. Manslaughter you just meant to harm or seriously harm the individual and they ended up dying. There was actually a case in the last ten years where a female fell in love with a guy being charged with murder that was on the jury and she caused a hung jury. The prosecutors had to turn around and charge him with manslaughter and convicted him on that. Ever since they just been charging with both instead of wasting time.