26.Newer techniques

POLYGRAPH (Lie Detector)

• Definition: A device that continuously records physiological variables such as blood pressure, heart rate, respiration, and electrodermal response (EDR) during questioning to detect lies.

• Electrodermal Response: Also known as Galvanic Skin Response (GSR) or Skin Conductance Response (SCR), indicative of skin moisture levels.

• Purpose: Measurements indicate anxiety linked to sympathetic stimulation during potential deception. However, anxiety from other causes can lead to unreliable results.

• Also Known As: Psycho-Physiological Detection of Deception (PDD).

Procedure

• Setup: Subject seated with a pneumatic rubber tube on the chest, blood pressure cuff on the arm, and electrodermal electrodes on fingers.

• Testing Techniques:

  • Relevant/Irrelevant Technique (RIT)

  • Control Question Technique (CQT)

• Question Types: Includes irrelevant (IR), probable lies (PL), and relevant questions (RQ).

Accuracy and Admissibility

• Claimed Accuracy: Examiners report about 90% accuracy.

• Court Admissibility:

  • In the US, left to individual jurisdictions.

  • In the EU, Australia, Canada, and England, typically not considered.

  • Indian courts show reluctance to accept polygraph results.

BRAIN FINGERPRINTING (Brain Mapping)

• Definition: Quantitative EEG (QEEG) measures the brain's electrical activity for crime knowledge detection.

• Inventor: Lawrence Farwell.

• Purpose: Indicates presence or absence of information related to a crime, not guilt or innocence.

Procedure

• Setup: An elastic cap with 19 sensors is placed on the subject's scalp connected to an EEG measuring device.

• Stimuli: Subjects view sounds, words, phrases, or pictures on a screen; EEG responses are recorded and analyzed.

• Advanced Method: Memory and Encoding Related Multifaceted Electroencephalographic Response (MERMER)

Applications

1. Criminal Investigation: Determining truthfulness or revealing facts.

2. Medical Evaluation: Early detection of Alzheimer’s and other degenerative diseases.

3. Advertisement Effectiveness Evaluation.

4. Security Screening: Military and intelligence employee evaluations to counter terrorism.

5. Insurance Fraud Detection.

Brain Signature Profiling (BSP)

• Developed by C.R. Mukundan in 2003.

• A procedure similar to brain fingerprinting.

Narcoanalysis

• Definition: A procedure to gather information from an individual in a natural sleep-like state.

• Principle: Neutralizes a person's ability to lie using imagination by making them semiconscious.

• Procedure:

  • Inducing a trance-like state using sodium amytal or thiopentone sodium (truth serum).

  • Dosage: 2.5 - 5% solution administered slowly via intravenous route.

  • Alternatives:

    • a) Scopolamine hydrobromide 0.5 mg subcutaneously.

    • b) 100 mg sodium seconal + 15 mg morphine + 0.5 mg scopolamine hydrobromide.

  • Dosage is dependent on sex, age, health, and physical condition of the individual.

Team Required for Narcoanalysis

• A multidisciplinary team includes:

  • Anesthetist

  • Psychiatrist

  • Clinical/Forensic psychologist

  • Audio-videographer

  • Supporting nursing staff.

Legal Aspects of Narcoanalysis

• Supreme Court ruling: Tests should not be conducted without the individual's consent.

• Results may not be admissible as evidence, even with consent.

• Methods deemed illegal and against the constitution as per Article 20(3): Individuals cannot be compelled to be a witness against themselves.

• In 2007, a Central Government committee reported these procedures as unscientific and unsuitable for criminal investigation.

Virtual Autopsy (Virtopsy)

Definition and Origin

• Virtopsy is a non-surgical postmortem technique used by forensic pathologists and radiologists.

• Coined term combines "virtual" and "autopsy", credited to Pro. Richard Dimofer from the University of Bern, Switzerland.

Procedure and Imaging Techniques

• A bloodless procedure visualizing and documenting findings.

• Applicable in various cases: natural deaths, mass accidents, gunshot injuries, and child abuse.

• Imaging methods include:

  • Computed tomography (CT)

  • Magnetic resonance imaging (MRI)

  • Postmortem angiography

  • Semi-microradiography

• 3D surface scanning integrates body surface documentation with 3D scene scans.

• CT highlights foreign objects, hidden fractures, and air embolisms, whereas MRI provides detailed soft tissue analysis.

• Combination of CT, MRI, and 3D scans needed for comprehensive findings.

Applications of Virtopsy

• In 2003, virtue methods were applied to a 3000-year-old mummy to ascertain death details.

• Established a modern forensic pathology toolbox for morphological investigations.

• Techniques include:

  • Multislice computed tomography (MSCT)

  • Multiplanar reconstruction (MPR)

  • Volume rendering technique (VRT) for examining various injury types.

• Used for identifying injuries in cases of gunshot wounds, explosions, child abuse, and decomposed bodies.

• 3D documentation assists in matching weapons and analyzing injury causation.

• Provides reconstructed images for cases such as strangulation, detailing position, marks, and associated injuries.

• Typical drowning cases can be analyzed by virtopsy.

  • Emphysema aquosum

  • Retrosternal touching of upper lobe of lung

  • Water in GIT

MALDI-MSI (Matrix Assisted Laser Desorption Ionization Mass Spectrometry Imaging)

• Used to detect condom lubricant in fingerprints, particularly in cases where rapists attempt to evade DNA evidence.

Nicotine Detection from Fingerprints

• A method developed in the UK detects smoking through chemical traces left on fingerprints.

• Involves dusting fingerprints with gold nanoparticles that bind to cotinine, a nicotine metabolite.