They like videos of chaos and screaming.
They like their photo shown.
They don't like stories about the victims that make the victims seem like they're human. What they were doing before the shootings, things they did with their lives, etc.
They don't like stories about the community itself that aren't just about the event (shooting).
I noticed NPR does a lot of stories about the the victims.
Nothing should be legally restricted, but I think news orgs can do their job 100% and still participate in a potentially helpful manner. To be clear there is no science that says doing any of these things reduce any amount of shooting or such, but it seems like a reasonable theory that if they see shootings result in coverage they don't like, it might discourage them if they think they won't get what they want.