Result is a permanent cancellation? Does that mean the match is nullified or the winner at the time wins? Either way, one team could draw a strategic black card. Seems like cancellation of the match is not the correct outcome. What about penalizing the harassing team? A red card result for the team (down a player for the next game). This seems like an odd way to handle abusive behavior from parents. Abandoning the current game may be good if parents are behaving that way, but there needs to be a serious consequence for the parent's team too. Otherwise it will just be another tool.