Cops in school cause changes.

But not the changes everyone was hoping for.

Police are police. They've been trained in a certain way to do a job that is more often than not dealing with criminals, very often dangerous as hell, and involves the chance (remote though it may be) that the officer will have to use his weapon to kill someone. To keep checks and balances aligned, police operate under strict rules and the laws are written to protect the innocent, etc.

Students are not criminals. Students are not committing "assault" but rather are "horsing around".  Johnny didn't commit "assault and battery", he hit Jack because Jack said his mother was fat and neither boy was serious.

When the administration gives up its responsibility and hands over discipline to the police, then you have created a bad place. Putting a school under police patrol changes the attitude, mood and responses of the administration in the 99.995% of the day that doesn't involve actions serious to warrant police action. The rest of the time? That hired gun wouldn't do jack squat.

From NYTimes, via Joanne Jacobs:

Since the early 1990s, thousands of districts, often with federal subsidies, have paid local police agencies to provide armed “school resource officers” for high schools, middle schools and sometimes even elementary schools. Hundreds of additional districts, including those in Houston, Los Angeles and Philadelphia, have created police forces of their own, employing thousands of sworn officers.
. . . “There is no evidence that placing officers in the schools improves safety,” said Denise C. Gottfredson, a criminologist at the University of Maryland who is an expert in school violence. “And it increases the number of minor behavior problems that are referred to the police, pushing kids into the criminal system.”

Joanne:

In the wake of Newtown, many districts are hiring police officers to guard schools. But once they’re on campus, cops usually end up enforcing discipline. We are criminalizing our children for nonviolent offenses,” Wallace B. Jefferson, the chief justice of the Supreme Court of Texas, said in a speech to the Legislature in March.

And you wonder why the kids don't take the administration all that seriously. It has abdicated in favor of the guy with the gun.

When a 14-year-old boy “angrily” threw a football at another boy’s leg, middle school officials called the police, who arrested the boy for assault. The other boy was not injured. There was no real explanation as to why the incident was considered serious enough to involve police. The police report states that the unnamed juvenile suspect appeared “angry.”