The National Criminal Justice Reference Service recently published a literature review and secondary data analysis entitled, “The Private Security Industry:  A Review of the Definitions, Available Data Sources, and Paths Moving Forward.”

The Private Security Industry

Executive Summary:

The private security industry is a crucial component of security and safety in the United States and abroad. Today, private security is responsible not only for protecting many of the nation‘s institutions and critical infrastructure systems, but also for protecting intellectual property and sensitive corporate information. U.S. companies also rely heavily on private security for a wide range of functions, including protecting employees and property, conducting investigations, performing pre-employment screening, providing information technology security, and many other functions.

In the past four decades, a series of reports and studies have examined private security agencies and personnel (i.e., Kakalik & Wildhorn, 1971a, 1971b, 1971c, 1971d; Cunningham, Taylor, & Hallcrest Systems, Inc., 1985; Cunningham, Strauchs, Van Meter, & Hallcrest Systems, Inc., 1990). These studies helped redefine the roles of private security and documented the growth and trends in the industry as a whole. However, these studies have become outdated, and there continues to be a significant need for more detailed and timely information, especially when considering the increasing range of roles played by private security. Moreover, the survey methodologies employed by some prior data collection efforts have produced data that are not generalizable to the population or that are potentially subject to nonresponse bias. Therefore, how well one can use these sources to make inference to private security as a whole is unknown. Currently, there is no existing data source that provides detailed information about private security—beyond basic demographics—that is not methodologically flawed due to the design or high nonresponse rates.

The Bureau of Justice Statistics (BJS), an independent statistical agency located within the U.S. Department of Justice, launched a design project to assess the feasibility of conducting a National Private Security Survey (NPSS). This report was developed as part of the design work. It provides a review of the literature on private security, including major trends, demographics, collaborations with law enforcement, budgeting and licensing, legal authority and powers within private security, and security operations. The report also presents an analysis of the availability and quality of secondary data on private security including a review of all available private security data from government sources, commercial sources, and research or academic sources. As part of this review, the report examines the methodology used to collect data on the private security industry and provides an assessment of the data quality.

The review suggests that suitable data are available on certain aspects of the private security industry. However, some components of the private security industry have not been studied in detail, while others have been studied but the existing data are either inconsistent or outdated. Based on the review, the following conclusions were generated:

1) Employee Demographics. Overall, high-quality demographic data have been collected in existing surveys; however, variations in the survey methodology and definitions of private security across these surveys produced some discrepancies in the estimates.

2) Budgeting and licensing. Budgeting and licensing information on contract security firms was substantial, compared to information for companies with a proprietary security force.

3) Private security powers. An insufficient amount of comprehensive data has been collected on private security powers; therefore, there is a significant need for information in this area.

4) Security operations. One of two secondary data sources provided information on security operations topics. Although one of the survey designs was methodologically sound, the response rate created a potential for biased estimates.

As a result of these findings, we offer the following recommendations for the design and implementation of a national survey of the private security industry:

1) Develop a clear definition of private security. When conducting a national data collection effort such as the NPSS, a succinct definition of private security should be developed with an understanding that the definition used may result in the collection of data that are different from those currently available.

2) Cover a broad range of topics.  A targeted, national study of the private security industry should cover a broad range of topics in order to minimize any potential measurement error caused by combining data from multiple sources that use different definitions of private security. Therefore, it is important that a future study not only fill in the recognized information gaps on private security (e.g., private security powers and security operations), but also obtain reliable and updated statistics, such as employee demographics, that are sufficiently covered by other surveys.

3) Utilize a rigorous data collection methodology. Future studies should also seek to address methodological and response rate challenges that affected past data collection efforts. This should include the development of a national sampling frame that provides more representative coverage of the companies to which inference will be drawn. Furthermore, procedures must include non-response follow-up to ensure a reasonable response rate.

4) Conduct the survey periodically. Studies that examine private security consistently over time would provide a significant advantage. This could be achieved either by examining a cohort of companies over time or drawing a new nationally representative sample of companies each time the data collection is fielded. Regardless of the approach, a set of studies conducted over time will better inform how private security changes in the size and characteristics of the industry, as well as the changing role and function of private security in the United States. These trends in the industry have both economic and policy implications.

In summary, this report provides recommendations for how future data collection efforts, such as the NPSS, can build on past efforts to increase knowledge of the private security industry and yield higher quality and more consistent data over time. The relevance of private security to our criminal justice system and to our nation‘s safety and security requires that we collect more consistent and timely information on the private security industry. This should include tracking of the functions and roles of private security as well as their intersection with policing, corrections, homeland security, and other relevant areas. By building on and improving upon past data collection efforts, we can ensure that the information that is collected is accurate, generalizable, and useful to the private security field, as well as to federal agencies and policymakers, and others with an interest in private security data.