In 1963, Milgram conducted a study whereby participants were asked to administer an electric shock to another participant (who was actually a confederate) upon incorrectly pairing words. Each time a the pairing was incorrect, the voltage of the electric shock increased to deadly levels. One key limitation of Milgram's study of obedience was the violation of ethics associated with the procedure. When the participants asked to leave the study, they were prodded by the researchers, saying anything from 'please continue' to 'you have no choice but to continue'. This meant that the participants did not feel as though they had a right to withdraw, violating ethical guidelines.However, due to the controlled laboratory nature of the experiment, every participant completed the exact same procedure, therefore should this study be repeated in future, findings should be similar, thus increasing the reliability of the findings.