SCP refers to a set of circumstances in which the environment is conducive for a crime to occur. Three basic factors must exist for a situational crime to be possible: motivated offenders, suitable targets and a lack of guardians or visible security. Many studies have demonstrated that use of metal detectors has significantly decreased situational crime, not only on college campuses but in elementary, middle and high schools, as well.
Some critiques contend that metal detectors may only give the appearance of ensuring safety. Metal detectors alone may not provide sufficient protection for students and staff; many researchers have suggested using locked doorways and entry ways into dormitory and school buildings, having private security patrol residence hall and classroom building hallways, providing a security escort to students who feel unsafe traversing campus and providing better lighting and more convenient emergency phones.
Since the early 1990s, federal law has required colleges to report actual crime statistics to the U.S. Department of Education together with the security measures taken. These statistics point to the need for prevention. In order for prevention to be effective, a college community must recognize that crime can and does happen anywhere. Metal detectors will assist in identifying those individuals that are carrying guns or knives made of materials which trigger sensors on the metal detector, but there are many other threats that the machines cannot detect. Weapons made of plastics or composite materials may be undetectable, as would conventional items that may be used as unconventional weapons. Metal detectors are only one part of the total picture of crime prevention on campus.
Although perhaps not enough on their own, metal detectors still play an enormous role in campus safety. Metal detectors reduce the number of weapons brought onto college campuses or into residence halls or school buildings. Also for those individuals who do try to bring weapons onto campus, the metal detectors provide the opportunity to seize the weapon, so that person is discouraged from trying the same thing again.