What practice was implemented to prevent imposters from taking civil service tests in the U.S.?

The practice of systematic fingerprinting was implemented to prevent imposters from taking civil service tests in the U.S. This method ensures that each individual taking the test can be accurately identified through their unique fingerprint patterns. By using fingerprints, authorities can verify the identity of test-takers, significantly reducing the risk of someone impersonating another individual to take a civil service exam.

This practice is particularly effective because fingerprints are distinctive and do not change over time, making it a reliable biometric measure. Once a candidate’s fingerprints are recorded and associated with their identity, any attempt at impersonation can be easily detected. The systematic nature of this approach means that it was arranged as a standard procedure across various testing environments, forming a key part of the process for establishing the integrity and authenticity of civil service examinations.

Other practices, while useful in different contexts, do not provide the same level of authentication specific to identifying individuals during testing scenarios.