What Is the Minnesota Multiphasic Personality Inventory–3 (MMPI-3)?

By Mark D. Lerner, Ph.D.

Clinical, Forensic, & Police Psychologist

Founder, Law Enforcement PEPtalk

Chairman, The National Center for Emotional Wellness

The Minnesota Multiphasic Personality Inventory–3 (MMPI-3) is the most widely used and empirically supported objective personality assessment in law enforcement pre-employment psychological evaluations across the United States. It's a standardized, norm-referenced psychological test with an extensive and continuously updated research base.

The MMPI-3 is designed to assess personality structure, emotional functioning, behavioral tendencies, and the possible presence of clinically significant psychopathology that may be relevant to psychological suitability for police work. It' not a “pass–fail” test, nor is it intended to diagnose candidates. Instead, it provides objective data that psychologists integrate with clinical interviews, background information, and other assessment tools.

Test Structure and Purpose

The MMPI-3 consists of 335 true/false items, a streamlined revision of earlier MMPI versions, developed to improve clarity, efficiency, and cultural relevance while maintaining strong psychometric integrity.

A critical component of the MMPI-3 is its validity scales, which evaluate how an individual approaches the test—not just what they endorse. These scales assess factors such as:

• Response consistency

• Over-reporting or exaggeration of symptoms

• Under-reporting or minimization of problems

• Attempts to present oneself in an unrealistically favorable manner

In pre-employment police evaluations, the most common interpretive concern is not psychopathology, but response credibility—particularly profiles suggesting excessive defensiveness or impression management (often referred to as “faking good”).

A Critical Warning About “Preparing” for the MMPI-3

Candidates are sometimes tempted to “practice,” research test items, or attempt to outsmart the instrument. This is strongly discouraged.

The MMPI-3 was specifically designed to detect inconsistent, coached, or strategically altered responding. Attempts to manipulate results frequently create validity scale elevations that raise more concern than honest endorsements ever would. In police psychology, credibility matters as much as content.

Best Practice Guidance for Candidates

The most effective—and safest—approach to the MMPI-3 is straightforward:

• Be honest and consistent

• Read each question carefully

• Answer what is being asked—nothing more

• Do not overthink or search for hidden meanings

• Do not try to portray yourself as flawless

Law enforcement agencies use the MMPI-3 because policing is psychologically demanding and requires emotional regulation, judgment under stress, impulse control, and interpersonal stability. A realistic, human profile is not only expected—it is preferred.

Final Perspective

The MMPI-3 is not designed to trick candidates, nor to disqualify psychologically healthy individuals. It's a sophisticated, evidence-based tool used nationwide to support public safety, officer wellness, and sound hiring decisions.

The best advice is simple, ethical, and scientifically sound:

Answer honestly. Let the test do what it was designed to do.