The event took place in Canada. As such, and very generally speaking, for any participants, the Criminal Code of Canada (CC) would apply; and if those participants were 18 or older, the CC’s prosecution and sentencing provisions would also apply. However, any accuseds under the age of 18 would fall under the provisions of the Youth Criminal Justice Act (YCJA). It is important to understand that the CC and the YCJA work together, in the sense that the CC contains all possible charges that can be laid against anybody of any age, but the YCJA determines how those charges are prosecuted and sentences determined when the accused is under 18.
Turning to the CC first, we see that under s. 271, the Crown can elect to prosecute a charge of sexual assault (the term used by the CC instead of “rape”) in a couple of different ways. I wouldn’t even hazard a guess as to how the Crown would elect to proceed, as age and past offenses may play a role in the Crown’s election decision, and various age-related defenses may be advanced by the accuseds under CC ss. 150.1 through 153. It should also be noted that some of the possible charges under CC ss. 150.1 through 153 might be able to be laid also, in place of (or perhaps alongside of) CC s. 271. There are also probably charges possible against those who posted photos on Facebook under CC s. 163.1 (child pornography).
The YCJA is a different beast altogether. Its primary purpose is to ensure that youth can be prosecuted for crimes, but in a slightly different way than adults. Ideally, the YCJA allows youth criminals (aside to Cat Whisperer: the term “young offenders” is no longer used officially) to be prosecuted for crimes committed under the CC, but with the possibility of having their records wiped by the time they hit 18. This does not necessarily occur, however; see YCJA ss. 61 through 81 as regards prosecuting youth as adults for presumptive offenses (defined at s. 2(1) of the YCJA), which some of the CC charges might be.
Note that if drugs were involved, there might even be charges possible under the Controlled Drugs and Substances Act (CDSA). Unfortunately, the news story was sketchy on the drug angle and I have to get to a few things today, so I won’t discuss the CDSA and its schedules right now.
Again, and honestly, I have no idea how this will all shake out, but I thought it worthwhile to take a fast look (key word: fast; unfortunately, I don’t have the time nor the information to analyze this fully) at the legislation that will govern the array of charges that can stem from this event, and also to provide links to the applicable legislation. I should add that while I am very familiar with the CC, I never dealt with youth crime, so my knowledge of the YCJA isn’t what it could be and I might be missing something in it. And, we only have the linked news story to rely on for facts–there may be something in facts not reported in the news item that could give rise to entirely different CC or CDSA charges and YCJA provisions. But I hope this all aids the discussion somehow.