The left is quite proud of its love of science. Their beliefs, their policy proposals, their wordview is based on science, or so they say. As such, science should be the sole objective measure of what is good for the people, and what is not.
The school shooting in Parkland, Florida has raised the question of whether mass attacks on schools are getting more frequent, and more deadly. If one were only to follow the press coverage of the issue, then the impression would be that schools are more prone to shootings than ever. But the research says that's just not so.