The Voigt-Kampff Empathy Test was a test designed to distinguish androids from humans by determining the subject's ability to empathize. The test was not perfect, as some humans with mental illnesses, such as schizophrenia, could conceivably fail.
The Voigt Empathy Test was originally developed by the Pavlov Institute in the Soviet Union after some T-14 androids had been able to remain undetected for up to a year. In around 1989/2018, the Voigt scale was altered by Lurie Kampff, establishing the Voight-Kampff Altered Scale as the primary method of testing.
In early 1992/2021, bounty hunter Dave Holden performed the test on three Nexus-6 androids. The third, Max Polokov, shot Holden during testing and escaped. Rick Deckard took up Holden's assignment and performed the test on Rachael Rosen, Luba Luft, and Phil Resch.
Behind the scenes
The test originally appears in Do Androids Dream of Electric Sheep?, then in the film adaptation, Blade Runner, where its spelling is slightly altered to Voight-Kampff, although the original spelling is retained in continuation novels written by K. W. Jeter.