Many employers use personality tests to identify job-related characteristics, such as maturity or emotional stability. But these tests can carry legal risk when applied incorrectly.
If you use personality tests, make sure that you can show a strong relationship between job performance and a particular personality type. You need to show a business necessity for the testing and prove the tests' validity, i.e. how well they measure what they purport to measure.
Usually, when people try to contest such tests, they complain about discrimination or cultural bias. In the following case, however, the employee unsuccessfully tried a new tactic: She claimed that the personal nature of psychological tests violated her constitutional right against unreasonable searches.
Recent case: A prison required a corrections employee to take a probing psychological test to keep her job. She sued, arguing that the two-hour test violated her Fourth Amendment right to be free from unreasonable searches and seizures.
An appeals court didn't buy her argument, though. "We do not think that the Fourth Amendment should be interpreted to reach the putting of questions to a person, even when the questions are skillfully designed to elicit ... personal private information," the court wrote. Such tests are widely used for employees in sensitive positions, the court noted. (Greenawalt v. Indiana Department of Corrections, No. 04-1997, 7th Cir., 2005)