The zero-tolerance policy in public schools was mandated in 1994 under the Gun-Free Schools Act. This policy requires that a student must be expelled from school for a year if caught after having been in the possession of a weapon. Following a string of violent mass shootings at schools, the zero-tolerance policy was purposed to help return schools to the “safe” environment they once were. Many changes were also made in schools to accompany the policy – metal detectors were installed, increased police presence in and around schools, as well as harsh disciplinary actions were imposed on students for minor offenses. Some critics of the policy have debated against its effectiveness - zero-tolerance was designed to be part of a more inclusive program directed at preventing school violence. However, many schools only focused on the punitive aspects and lost sight of creating these prevention programs.