The group who warned against watching the episode was the Newtown Action Alliance. Their statement was:
“According to someone who blogs for an Internet site that is a TV spoiler site, the TV show, “Glee” that airs tonight on Fox is going to depict a school shooting from the vantage point of the students hiding in the dark. He said it is extremely harrowing and it even freaked him out and he’s not from here.
I would suggest if you do watch this TV show to either not watch it tonight or watch with caution.”
I don’t think there’s anything wrong with letting people who might be traumatized by the actual shooting that there would be a “harrowing” tv episode about a shooting, and that they should judge for themselves whether they want to watch. I think they should have addressed the warning in that way, instead of essentially telling everyone not to watch. That was inappropriate.
There was a similar situation many years ago with Buffy the Vampire Slayer, in which they had scheduled an episode about a school shooting (Earshot) to air a few days after the Columbine shooting took place. The episode had been written, shot, and scheduled long before the actual shooting took place, but show creator Joss Whedon had it pulled because of the timing. It was ironic, because of course the theme of the show was positive, and it addressed the emotions of teens who might want to commit this kind of act – the point being that it could help someone decide not to do that. But he didn’t want to further traumatize those who were affected by the real shooting, and he didn’t want to be seen as capitalizing on the shooting. So it aired only many months later. In that context, I ask myself whether the Glee episode was planned before or after the shooting, and whether it aired too soon. I don’t particularly think that it aired too soon.