School safety can be a controversial subject. Although everyone agrees that safe schools are important and essential in every community, not everyone agrees on how to achieve safe schools. Zero tolerance policies began emerging in the 1980s and 90s in response to the increased efforts in the government's war on drugs, as well as part of the Gun Free Schools Act.
Over time, many schools expanded their zero tolerance policies to include other behaviors including fighting, or possessing drugs or alcohol, and even less serious offenses. After the tragic Columbine shooting in 1999, many more schools started instituting zero tolerance policies for students caught carrying weapons. However, now that there is decades of data for researchers to review and analyze, zero tolerance policies have come under the microscope.