Did you read the blog in question? Are you in possession of the full facts of the case? Do you know those involved? Or have you formed your opinions based on some gossippy trash reporting.
There is almost always far more to stories like this than the reporting has us to believe. That's because the reporting is pushing an agenda. Which internet hate mobs etc absolutely love.
So you dispute the story and the reporting is "pushing an agenda"? Why do I have the feeling that you don't think that the "teacher" was wrong in what he did?
Having read some of the blog, it certainly looks like he's a kid with issues. So I'm not surprised the teacher called the university to warn them.
Not sure he really should have called the police, but it's up to him isn't it. But as I said, there's very likely far more to the story than just a blog.
If for example the story was "teacher calls police after student damages property / makes threats / brings knife to school / etc etc, and also shows police his weird ranty blog", then it wouldn't fit with the 'internet hate mob' agenda.
There is almost always far more to stories like this than the reporting has us to believe. That's because the reporting is pushing an agenda. Which internet hate mobs etc absolutely love.