Private security guards work with the police department to counteract crime and terrorism. They became a necessity at the present time since issues of security have an increasingly important impact on the public awareness. Private security can be provided by contract guard agencies, in-house guards or both.
The article “Applications of Forensic Science in Private Security” by Danielle Sapse from John Jay College of Criminal Justice (Department of Law, Police Science, and Criminal Justice Administration) published in the Beijing Law Review (Vol.4 No.4 2013) gives a description of the methods of forensic science as used in the private security business.
Forensic science applies scientific methods to the solving of crimes. These methods include fingerprinting, drug analysis, DNA (Deoxyribonucleic Acid) studies, ballistics, arson and explosive investigations, and studies of glass fragments.
Fingerprinting and urine, saliva, or hair analysis for the presence of drugs are essential for the hiring of private security guards in order to establish their suitability for the position. Such information can also be useful in determining if a candidate for a guard position was ever convicted of a felony which would prevent his or her being hired as a guard.