Some employers use personality tests such as the Myers-Briggs Type Indicator personality assessment tool, the NEO-Personality Inventory or the Personality Characteristics Inventory to better understand personality traits of job candidates. Advocates say workplace personality tests help employers screen out applicants who might be a bad fit for the job. Opponents argue that the tests typecast people, lack credibility and invade applicants' privacy.

Applicant Screening

Personality tests are a legal way for employers to screen job candidates and uncover possible behavior issues, such as tardiness, violence or dishonesty, reports former English professor Susan Stabile in the University of Pennsylvania Journal of Labor and Employment Law. In 1988, federal law banned the use of lie detector tests by employers, so personality tests became the next best option. The tests examine five key traits -- emotional stability, extroversion, cooperation, open-mindedness and scrupulousness -- according to Cornell University.

Better Interviews

Advocates argue that personality tests help employers conduct more robust job interviews. Hiring managers have a better idea of what to address, such as a candidate's soft skills like troubleshooting, problem-solving, time management, self-confidence, flexibility, organization, communication and work ethic, suggests the human resources consulting firm Helios HR. They help employers understand what motivates job candidates and determine whether they're team players.

Labels and Typecasts

Opponents argue that workplace personality tests typecast individuals, resulting in unfair speculations and expectations, suggests Lily Garcia, employment law and human resources specialist, in an article in The Washington Post. Job applicants might feel trapped or limited by their personality results or fear they'll experience discrimination. For example, an applicant who tests as an introvert might not get a sales job, even though she has the education, skills, experience and previous results to back her qualifications. Some applicants say that the tests invade their privacy because they must answer personal questions that have little or nothing to do with work responsibilities.

Unreliable and Unproven

Some who oppose the tests argue that they're unreliable and untrustworthy. For example, job applicants may fake their answers and lie to make themselves look better, according to Cornell University. Workplace personality tests may not accurately assess how successful or productive a job candidate will be. According to a 2007 study at Michigan State University, business professor Frederick Morgeson determined that there was a near zero correlation between personality tests and job success rates -- 0.03 to 0.15. Personality tests also take time to conduct and interpret, and cost between $100 and $5,000 per candidate, according to Helios HR.