https://www.techdirt.com/articles/20180530/14110039944/school-cant-take-joke-turns-student-over-to-cops-listing-school-sale-craigslist.shtml

Recent school shootings have led to heightened reactions from school officials and law enforcement. An over-correction of sorts -- thanks to the shooter in Florida having been brought to law enforcement's attention several times prior to the shooting -- has resulted in the arrest of hundreds of students across the nation.

The problem isn't so much treating potential threats as credible until proven otherwise. The problem is there's so very little subtlety applied. Things that should not be perceived as threats are, and even when they're determined to be either unfounded or not actually a threat, some schools decide their misperceptions are more important than the reality of the situation. (h/t Reason)