L29 Polygraph

Question 1

Polygraph

Answer 1

POLYGRAPH (or LIE DETECTOR) works on the premise that when people lie, they get nervous, and when people get nervous, their body reacts in involuntary ways (blood pressure, heart rate, respiration, and skin conductivity) that can be measured by a POLYGRAPH.

• The PROBLEM is that there are many people (good actors and people comfortable with lying) who do NOT get nervous when they lie.
  
  • Ex: Gary Ridgeway, the Green River Killer, had undertaken Polygraphs after killing many people and passed. He was later taken down only from DNA evidence once the technology had evolved.
• IMPORTANT: The PROFESSOR thinks POLYGRAPHS are GARBAGE!

Polygraphers follow several premises:

• Especially when there are known consequences to lying, people get nervous when they lie.
• Conversely, those who are innocent tend to give clear and concise answers.
• People can’t look you in the eye when lying.
  
  • Evidence suggests that not even skilled questioners are efficient at detecting deception on the basis of someone’s verbal and nonverbal cues.
  • Research suggests that most liars are caught because it becomes too difficult to continue a lie and they haven’t made sufficient preparation to avoid being detected.
  • Seven qualities that make an effective liar:
  1. Has a well-prepared story
  2. They were original with what they’re saying
  3. They think quickly when the need arises
  4. They tend to be very eloquent in their storytelling skills
  5. They have an excellent memory for what they have said before
  6. They generally don’t experience emotions such as fear or guilt by their lies
  7. They have excellent acting ability

POLYGRAPH ACCURACY:

• Studies estimate that the polygraph typically MISIDENTIFY:
  
  • At least 15% of LIARS as truth-tellers
  • At least 15% of TRUTH-TELLERS as liars

Question 2

What Happens When We Lie, Autonomic Nervous System

Answer 2

Polygraphs collect date from three systems:

1. Respiratory system (breathing)
2. Cardiovascular system (blood pressure and pulse rate)
3. Endocrine System – Sweat gland activity (galvanic skin response – electrical conductivity of your skin which is affected by how much you sweat)

• Additionally, in the newer digital types of polygraph machines, they can also use a sensor pad which is placed under the person who’s being interviewed. The pad measures ‘FIDGITINESS’ which would presumably occur when you are telling a lie.

Question 3

3 Types of Polygraph Questions (Irrelevant, Relevant, Comparison) and Examination (Comparison, Peak Stress, Guilty Knowledge)

Answer 3

There are THREE TYPES of QUESTIONS on a POLYGRAPH SESSION:

IRRELEVANT QUESTIONS (or First Time Questions) – Because these questions are structured to be emotionally neutral, they are used to establish a baseline state – meaning their typical state of nonarousal.

• Ex:“Is your name Joe Smith?”

RELEVANT QUESTIONS are those directly pertaining to the issue at hand.

• Softer language is used with the relevant questions than in the comparison questions.

COMPARISON QUESTIONS – are questions designed to threaten a truthful person – designed to elicit a reaction from someone who may feel threatened by a question.

• Ex:“Have you ever stolen money from someone who trusts you?”
• COMPARISON QUESTIONS are then used to compare to the reaction seen from the RELEVANT questions.

THERE are THREE TYPES of POLYGRAPH TESTS:

1. The COMPARATIVE QUESTIONS TEST is probably the MOST COMMON but the PROBLEM with it is that EVEN INNOCENT PEOPLE MAY REACT STRONGLY to threatening comparison questions.
2. The PEAK TENSION TEST is basically just a fishing expedition, a set of 5-9 yes/no questions.
   
   • ​The polygraph administrator asks the suspect about a detail that’s related to the crime and the examiner knows that the questions are related to exact details of the crime and they are searching for the questions that elicit the strongest response from the suspect.
     
     • They would follow up on the questions with the largest response.
3. GUILTY KNOWLEDGE TEST compares physiological responses to multiple-choice type questions about a crime. one of the choices for each question contains information known ONLY by the investigators and the person who committed the crime.

• Ex: Maybe they will flash pictures of different weapons on a computer screen and you would expect the perpetrator to be able to recognize the weapon that was used in a particular crime and respond (involuntarily) MORE STRONGLY to that than the other weapons.

NOTE FROM PROFESSOR: this technique actually has no legitimate scientific foundation whatsoever based on brain processes that underline memory but it’s used anyway by some polygraphers.

Question 4

Polygraph (Aldrich Ames, Robert Hanson Spies), Countermeasures

Answer 4

Some of this country‘s most prolific and dangerous spies such as ALDRICH AMES and ROBERT HANSON repeatedly passed polygraph tests

• Ames was a former CIA counterintelligence officer and analyst and he was convicted in 1994 for spying for the Soviet Union in Russia he compromised more CIA assets than any Soviet mole.
• Robert Hansen was a former FBI agent who also spied for the Soviets. He currently spends 23 hours a day in solitary confinement.
• Both of these individuals passed a polygraph with flying colors. They both knew the countermeasures needed to FOOL the EXAMINER.

POLYGRAPH COUNTERMEASURES:

• Can be physical or psychological
• The MOST COMMON countermeasures used either involves the use of pain or muscle tension.
  
  • Ex: In an effort to deceive a polygrapher – biting your lip or your tongue or subtly jabbing yourself with a pin that you inserted into your shoe to induce enough pain to provoke a physiological response that masks your response to questions from the polygrapher.
• MENTAL COUNTERMEASURES can include:
  
  • Attempts at DISTORTION of the EXAMINER’s WORDS in your head.
  • You may start counting backward from 100 while you’re being questioned or thinking about peaceful or arousing scenes while the examiner tries to ask you questions you’re trying to minimize or confuse the emotional impact of those questions.
• ​OTHER COUNTERMEASURES:
  
  • ​Control your breathing during relevant questions
  • Artificially increasing your heart rate during comparison questions by thinking of something scary or something exciting.
• MOST SCIENTISTS AGREE that there is NO SPECIFIC PHYSIOLOGICAL RESPONSE that is uniquely associated with lying.
• POLYGRAPHS HAVE BEEN SUCCESSFULLY CHALLENGED on several occasions in various jurisdictions on the basis of their scientific uncertainty.
• POLYGRAPHS do not rise to the level of reliability that’s required for scientific evidence and polygraph test are usually inadmissible as evidence.
• NONETHELESS, investigator still request suspects to undergo a lie detector test as part of a pre-criminal investigation.
  
  • Why would they do that if they can’t use that evidence in court?
    
    • It’s because what they’re trying to do is convince the person that they’re interviewing or who is undergoing this polygraph examination that this LIE detector has shown results that really don’t bode well for the person who’s being accused and that you should just simply come clean and it will all be over with.
      
      • That ACTUALLY WORKS in some cases.
• The MOST COMMON USE of the polygraph currently is in MONITORING SEX OFFENDERS.

Question 5

Polygraph Validity

Answer 5

How Valid is the Polygraph?

• There is almost NO support for the validity of the Polygraph from scientists, and yet most polygraphers will claim it’s 95-100% accurate.
• Scientists note that polygraph interrogations can’t be standardized and so accuracy for it can not be established.

Question 6

Polygraph Uses

Answer 6

Despite the lack of scientific support for the Polygraph, it is still used:

• …as an investigative tool
• …to screen applicants for jobs
• …to screen offenders especially sex offenders who are on parole to make sure that they are compliant for things such as not having contact with minors

The polygraph is still used by many police, FBI, CIA, businesses etc. to:

• …try to clear the innocent
• …identify the guilty
• …recover evidence
• …recover property
• …protect assets

Question 7

Sex Offender Monitoring

Answer 7

MONITORING SEX OFFENDERS is currently the most common use for the polygraph to make sure that they are following the conditions of probation or parole.

• Polygraph testing is sometimes used for REHABILITATION of convicted sex offenders to make sure that they are remaining compliant with not being around minors.
• Questions often focus on the offender’s thoughts, desires, impulses, and behaviors to gauge the likelihood that they will offend again in the future.