Not sure about the Toronto jursidiction but prosecutors sometimes overcharge hoping to extract a guilty plea on a lesser charge. This sounds to me like it could be a manslaughter situation or perhaps negligent homicide.
It reminds me that years ago I had to defend a road rage case involving a friend of mine. I was actually shocked by the charges laid against him because he is not a violent guy nor does he have a temper, but he misinterpreted a situation on the roadway and ended up causing an accident with another vehicle, on purpose. The prosecutors charged the shit out of it and the prosecutors in this particular court, which I will not mention, have a reputation as Neo Nazis who overcharge the shit out of everything. Anyways I went in there with guns blazing and copies of all the statutes he charged and basically in a nice professional way I told the prosecutor (in the privacy of his office) that he was full of shit, and why he was full of shit. I pointed out the lack of legally required elements present in the case, which must be proven under all the statutes that he charged. Anyways, with no rebuttal argument on his part, he offered me a plea deal on one of about 6 bullshit charges he had filed, where my client would pay a fine of $450 and plead to an infraction.
My initial reaction was to say "fuck you!" and ask for a trial date and tell him I would see him in court and hit him with some aggressive discovery requests, but I knew my client wanted to put the whole thing to bed. So I took the deal to him and he said to do it, and not to ask for a trial date.
The other thing is that in a high profile case that is in the media, there is often political pressure to overcharge cases. And what then happens, sometimes neither side budges and fears doing so, and an otherwise bullshit case is tried instead of settled because of artificial political pressure.