I agree. But, while there are criminals (so called wrong people) who can be avoided while hiring, there is nothing like right people because the right person at the wrong time could turn in to a criminal (there is always first time for everything. right?). In addition to all the technology, people should have defense mechanism such as pepper or some other spray. Finally, sadly, there is nothing like 100% effective method!! That does not mean we should not improvise and try to save at least a few occurences if not all.
