In the 1990s, crime rates dropped significantly, but media coverage of violent crime increased. As shootings, terrorism, and school violence appeared more and more in the news, people began to demand increased vigilance from teachers and administrators. The result was cops and metal detectors in schools, and an increase in zero-tolerance policies and referrals to law enforcement when students get out of hand.
At least, these things increased in schools with significant black or Latino populations. For white students, things kept on pretty much as they had been.
According to Penn State sociologist David Ramey, schools with large black populations were more likely to punish students than to try to treat them. What that means is that, while many white children who act out in class are treated as having ADHD or a learning disability, black kids are suspended, expelled, or arrested. For Latinos, the numbers for arrests and expulsions were lower, but the numbers of students who were treated for their misbehavior were still lower than in predominantly white schools.
Part of the issue lies in the fact that of the 60,000 schools that Ramey studied, the schools with the most problems, and the most minority students, were also the most disadvantaged. These were poor schools wherein rules were centralized at the district level, requiring all schools to handle things the same. Meanwhile, in better off school districts, individual schools could handle things on a case-by-case basis, and often did.
The use of top-down, zero-tolerance policies, the kind that result in expulsions and arrests instead of treatment and communication, has a deleterious effect on students. Students who are summarily punished for acting out are effectively criminalized, if they’re even allowed back into school they tend to develop the opinion that the system has failed them, if it’s not actively working against them. These students are less likely to go to graduate high school, much less go to college, and often fail to rise above the poverty level, subjecting a whole new generation to the same disadvantaged schools.