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Lie Detector Tests and Constitutional Rights in Criminal Justice

PYQs

8

Articles

1

Momentum

21

Phase IFoundation

Background

Overview

UPSC frequently tests the intersection of technology, law, and fundamental rights. This concept involves landmark judicial pronouncements, constitutional principles, and the evolving nature of criminal justice, making it highly relevant for GS2 (Polity, Judiciary) and GS3 (Internal Security, Science & Technology in investigation).

The use of scientific investigative techniques like polygraph, narco-analysis, and Brain Electrical Activation Profile (BEAP) tests in criminal investigations raises significant questions regarding fundamental rights guaranteed by the Indian Constitution, particularly the right against self-incrimination (Article 20(3)) and the right to personal liberty (Article 21). The Supreme Court has laid down crucial guidelines on their administration and evidentiary value.

Phase IIStatic core

Facts & tables

Key facts

Consent Requirement

Cannot be administered without the subject's free and informed consent, as established in Selvi v State of Karnataka (2010).

Constitutional Violation

Compulsory administration of these tests violates Article 20(3) (right against self-incrimination) and Article 21 (right to personal liberty, including mental privacy).

Evidentiary Value

Test results themselves are not admissible as substantive evidence of guilt, even if voluntarily administered.

Corroboration

Facts discovered as a direct result of such tests can be used as corroborative evidence under specific conditions (e.g., Section 23 of Bharatiya Sakshya Adhiniyam).

Reference table

Static syllabus anchors

TypeReference
Conceptual areaFundamental Rights
Conceptual areaJudiciary & Judicial Review
Conceptual areaConstitutional Amendments & Structure

Reference table

Institutions & roles

BodyRole
Supreme Court of IndiaInterprets the constitution and sets legal precedents regarding fundamental rights and investigative techniques
National Human Rights Commission (NHRC)Issues guidelines for the ethical and legal administration of lie detector tests
Central Bureau of Investigation (CBI)Investigates criminal cases and seeks judicial permission for administering such tests
Phase IIIExam lens

Prelims angle

Overview

Prelims angle: Multi-statement analysis

Prelims angle: Conceptual understanding

Quick revision

  • SC in *Selvi v State of Karnataka (2010)*: Compulsory tests violate Art 20(3) & 21.
  • Voluntary tests allowed with judicial magistrate consent & legal advice.
  • Test results not substantive evidence; discovered facts can corroborate.
  • NHRC 2000 guidelines provide safeguards for voluntary test administration.
  • Judicial discretion is crucial at all stages of trial for permitting such tests.

Elimination traps

Constitutional vs statutory — Distinguish between constitutional rights (e.g., Article 20(3), 21) which set limits, and statutory provisions (e.g., Bharatiya Sakshya Adhiniyam) which govern the procedural aspects and evidentiary value of such tests.

Check if created by Constitution or by Parliament.

High-confidence PYQs

2025Statement-based questions, Conceptual understanding

Consider the following pairs: Provision in the Constitution of India – Stated under I. Separation of Judiciary from the Executive in the public services of ...

Indian PolityOpen question

With reference to the Indian polity, consider the following statements: I. An Ordinance can amend any Central Act. II. An Ordinance can abridge a Fundamenta...

Indian PolityOpen question
2025Statement-based questions, Factual recall

Consider the following pairs: Provision in the Constitution of India – Stated under I. Separation of Judiciary from the Executive in the public services of ...

Indian PolityOpen question

With reference to the Indian polity, consider the following statements: I. An Ordinance can amend any Central Act. II. An Ordinance can abridge a Fundamenta...

Indian PolityOpen question
2024Factual recall, Conceptual understanding

Under which of the following Articles of the Constitution of India, has the Supreme Court of India placed the Right to Privacy?

Indian PolityOpen question
2021Multi-statement analysis, Conceptual understanding

Consider the following statements: 1. ‘Right to the City’ is an agreed human right and the UN-Habitat monitors the commitments made by each country in this r...

Indian PolityOpen question
2020Multi-statement analysis, Factual recall

Consider the following statements: 1. Aadhaar metadata cannot be stored for more than three months. 2. State cannot enter into any contract with private cor...

Indian PolityOpen question

Which one of the following categories of Fundamental Rights/incorporates protection against untouchability as a form of discrimination?

Indian PolityOpen question
2020Factual recall, Conceptual understanding

Consider the following statements: 1. Aadhaar metadata cannot be stored for more than three months. 2. State cannot enter into any contract with private cor...

Indian PolityOpen question

Which one of the following categories of Fundamental Rights/incorporates protection against untouchability as a form of discrimination?

Indian PolityOpen question
2018Conceptual understanding, Factual recall

Right to Privacy is protected as an intrinsic part of Right to Life and Personal Liberty. Which of the following in the Constitution of India correctly and a...

Indian PolityOpen question
2017Multi-statement analysis, Factual recall

Which of the following are envisaged by the Right against Exploitation in the Constitution of India? 1. Prohibition of traffic in human beings and forced la...

Indian PolityOpen question

Topic timeline

Fundamental RightsJudiciary & Judicial ReviewConstitutional Amendments & Structure
Prelims 2017· Multi-statement analysis, Factual recall

Which of the following are envisaged by the Right against Exploitation in the Constitution of India? 1. Prohibition of traffic in human beings and forced la...

Open question
Prelims 2018· Conceptual understanding, Factual recall

Right to Privacy is protected as an intrinsic part of Right to Life and Personal Liberty. Which of the following in the Constitution of India correctly and a...

Open question
Prelims 2020· Multi-statement analysis, Factual recall

Consider the following statements: 1. Aadhaar metadata cannot be stored for more than three months. 2. State cannot enter into any contract with private cor...

Open question

Which one of the following categories of Fundamental Rights/incorporates protection against untouchability as a form of discrimination?

Open question
Prelims 2020· Factual recall, Conceptual understanding

Consider the following statements: 1. Aadhaar metadata cannot be stored for more than three months. 2. State cannot enter into any contract with private cor...

Open question

Which one of the following categories of Fundamental Rights/incorporates protection against untouchability as a form of discrimination?

Open question
Prelims 2021· Multi-statement analysis, Conceptual understanding

Consider the following statements: 1. ‘Right to the City’ is an agreed human right and the UN-Habitat monitors the commitments made by each country in this r...

Open question
Prelims 2024· Factual recall, Conceptual understanding

Under which of the following Articles of the Constitution of India, has the Supreme Court of India placed the Right to Privacy?

Open question
Prelims 2025· Statement-based questions, Conceptual understanding

Consider the following pairs: Provision in the Constitution of India – Stated under I. Separation of Judiciary from the Executive in the public services of ...

Open question

With reference to the Indian polity, consider the following statements: I. An Ordinance can amend any Central Act. II. An Ordinance can abridge a Fundamenta...

Open question
Prelims 2025· Statement-based questions, Factual recall

Consider the following pairs: Provision in the Constitution of India – Stated under I. Separation of Judiciary from the Executive in the public services of ...

Open question

With reference to the Indian polity, consider the following statements: I. An Ordinance can amend any Central Act. II. An Ordinance can abridge a Fundamenta...

Open question

‘Intrusion into mental privacy’: How courts treat lie detector tests, amid NEET case plea

12 Aug 2026 · The Supreme Court in Selvi v State of Karnataka (2010) ruled that compulsory lie detector tests violate fundamental rights (Art 20(3), Art 21). Voluntary tests are permissible with safeguards (judicial magistrate consent, legal advice) but their results are not substantive evidence, only corroborative for discovered facts.

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Related topics

Current topic

Lie Detector Tests and Constitutional Rights in Criminal Justice

Often confused with

Judicial Review and Role of Supreme Court

Open notes

Practice writing on this topic

UPSC has asked 8 linked questions on Lie Detector Tests and Constitutional Rights in Criminal Justice in Mains. Write an answer to one — and get it evaluated.

See Mains PYQsEvaluate an answer

UPSC Prelims PYQs on Lie Detector Tests and Constitutional Rights in Criminal Justice

Practice official previous year questions asked by UPSC related to this concept.

Consider the following statements: 1. ‘Right to the City’ is an agreed human right and the UN-Habitat monitors the commitments made by each country in this r...

2021·Indian Polity
Solve

Right to Privacy is protected as an intrinsic part of Right to Life and Personal Liberty. Which of the following in the Constitution of India correctly and a...

2018·Indian Polity
Solve

Consider the following pairs: Provision in the Constitution of India – Stated under I. Separation of Judiciary from the Executive in the public services of ...

2025·Indian Polity
Solve

With reference to the Indian polity, consider the following statements: I. An Ordinance can amend any Central Act. II. An Ordinance can abridge a Fundamenta...

2025·Indian Polity
Solve

Which of the following are envisaged by the Right against Exploitation in the Constitution of India? 1. Prohibition of traffic in human beings and forced la...

2017·Indian Polity
Solve

Consider the following statements: 1. Aadhaar metadata cannot be stored for more than three months. 2. State cannot enter into any contract with private cor...

2020·Indian Polity
Solve

Which one of the following categories of Fundamental Rights/incorporates protection against untouchability as a form of discrimination?

2020·Indian Polity
Solve

Under which of the following Articles of the Constitution of India, has the Supreme Court of India placed the Right to Privacy?

2024·Indian Polity
Solve

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