The Polygraph Machine: Detecting the Truth

The video discusses the invention and history of the polygraph, a machine created by John Augustus Larson in 1921 to detect lies by measuring physiological stress responses. Despite its initial adoption by federal agencies, the polygraph's accuracy was questioned, leading to its exclusion as evidence in federal cases. During the Cold War, it was used to test suspected spies, but its reliability remained controversial. Notable cases like Aldrich Ames and Gary Ridgway highlight its limitations. Today, polygraphs are still used, but their accuracy is debated, and states decide their admissibility in court.

Who invented the polygraph and in what year?

• John Augustus Larson in 1921

• Thomas Edison in 1920

• Alexander Graham Bell in 1922

• Nikola Tesla in 1923

What was the main reason polygraph results were initially not accepted as evidence in federal cases?

• It was too difficult to operate

• The results were not scientifically verified

• It was invented by a student

• The machine was too expensive

During which period was the polygraph notably used to test suspected spies?

• World War I

• The Cold War

• The Gulf War

• The Vietnam War

Which double agent managed to pass the polygraph test twice?

• Robert Hanssen

• Aldrich Ames

• Gary Ridgway

• John Walker

What is the current stance on the admissibility of polygraph tests in court?

• They are only used in federal cases

• States can decide individually

• They are banned in all states

• They are universally accepted