California POST has conducted repeated statewide job analyses and empirical validation research establishing the behavioral attributes that predict peace officer performance. That research corpus is publicly available, legally codified in California regulation, and represents the most rigorously tested standard for peace officer behavioral selection in the United States. This review examines POST's research methodology, the legal status of its findings, and the national influence of its validation work.

Section 1: POST's Statutory Mandate

The California Commission on Peace Officer Standards and Training was established by the Legislature in 1959. POST is funded through the Peace Officers' Training Fund, which derives from penalty assessments on criminal and traffic fines rather than general tax revenue. POST is staffed by more than 130 personnel ^[9].

POST's statutory mandate is to establish minimum selection standards for California peace officers and to conduct research that results in the development of tests and procedures used by local agencies ^[1]. This is a research and standards body, not a product certification authority. POST validates constructs and criteria. POST does not endorse commercial instruments.

Section 2: The Job-Analytic Foundation

POST has conducted repeated statewide job analyses on peace officers and public safety dispatchers. Job analytic data was reanalyzed in conjunction with each revision of the Background Investigation Manual to derive the current set of essential peace officer attributes ^[2].

The background investigation dimensions codified in Commission Regulations 1953(b) and 1959(b) carry the force of law ^[3]. These are not advisory guidelines. They are statutory evaluation criteria that every California law enforcement agency is required to assess during the background investigation of peace officer candidates.

The dimensions were selected based on their specific amenability to assessment during the background investigation phase. POST's documentation notes that redundancy across selection stages, including the background investigation, hiring interview, and psychological screening, is intentional. It enhances measurement accuracy of the most critical attributes ^[2].

Section 3: The Psychological Screening Validation

POST's validation work extends beyond background investigation. POST commissioned a formal meta-analysis conducted by Ones, Viswesvaran, Dilchert, and Cullen providing empirical evidence for the validity of POST Psychological Screening Dimensions across law enforcement populations ^[4].

The screening dimensions were developed through POST's own psychologically-based job analysis using subject matter experts, including patrol supervisors and field training officers from agencies statewide. Regulation 1955 requires the use of POST Psychological Screening Dimensions in the psychological evaluation of all California peace officers ^[5].

The meta-analysis technical report established that integrity tests demonstrate mean true validities of .34 with overall job performance and .47 with counterproductive behaviors. Multiple measures of the same trait increase predictive validity by up to 50% depending on the number of scales combined ^[7].

Section 4: The Pre-Offer Assessment Boundary

POST's own guidance distinguishes between instruments lawful at the pre-offer stage and those reserved for the post-offer medical evaluation. The Resource Guide for pre-offer personality testing documents POST's statewide analysis of personal and interpersonal demands of the role. Subject matter experts rated competencies based on their importance to successful peace officer performance ^[6].

Section 1955 confirms pre-offer permissibility of normal-range personality trait assessment when the instrument is not designed to detect disabilities ^[5]. Biographical data collection, history verification, and behavioral pattern identification fall within the pre-offer permissible space as defined by both POST guidance and ADA case law.

Section 5: National Influence

POST has no statutory jurisdiction outside California. Empirical validity, however, is not jurisdiction-specific. The behavioral attributes that predict peace officer performance in California predict performance in the same role in other states because the role's essential functions, including legal authority to use force, arrest, detain, and surveil, are defined by substantially equivalent statutes in all U.S. jurisdictions.

POST's own documentation notes that its Psychological Screening Dimensions have influenced peer-reviewed research (Detrick and Chibnall, 2017; Sellbom, Corey, and Ben-Porath, 2020), legal decisions in other states (Brown v. Sandy City, Utah, 2014), and state regulations including Texas Administrative Code Title 37, Part 7, Rule 217.1 and Washington Administrative Code 139-07-030 ^[4].

The regulatory development history, documented in POST's Initial Statement of Reasons ^[8], confirms that the background investigation dimensions were developed from job analytic research and verified by background investigation subject matter experts. This genealogy establishes that the dimensions are empirically derived, not administratively imposed.

Section 6: Implications for Behavioral Screening Tools

Any behavioral screening instrument that operationalizes POST-validated constructs derives its defensibility from POST's published research foundation, not from vendor claims. POST does not endorse products. POST validates constructs. That distinction is critical for procurement evaluators and legal reviewers assessing whether a commercial screening instrument has an empirical basis.

The defensibility claim is this: the constructs are drawn from POST's validated research corpus, which was developed through repeated statewide job analyses, verified by subject matter experts, validated through meta-analytic research, codified in California regulation, and recognized by courts, researchers, and regulators in other jurisdictions. That claim is accurate, verifiable, and independent of any commercial vendor relationship.