Fiction has made detective work look simple. Sherlock Holmes followed a clue wherever it led. Hercule Poirot rebuilt a crime from details that seemed insignificant. Neither had to answer the questions that constrain a real investigator: Is the surveillance legal? Who authorised it?
These questions came up at the Supreme Court's July 31 judgment in Himanshu Chordia vs State of Rajasthan, where a bench of justices Sanjay Karol and Vipul M Pancholi examined material that purportedly showed a woman pursuing a relationship outside her marriage. The appellant had placed roughly 237 photographs and 92 videos before a trial court.
The bench, suspecting that the images and videos may have been procured through private investigators or detectives, flagged absence of any law governing them, even as their work increasingly involves surveillance, electronic evidence and personal data.
Terming the procurement of evidence through private investigators "an area sans regulation", the court said a mechanism was needed to deal with evolving methods of evidence collection. It directed that a copy of the judgment be sent to the Law Commission and the Union law ministry, and noted that investigators need some protection too — against allegations such as voyeurism.
No dedicated law in India…
India has no dedicated law regulating private detective agencies. But there have been previous court orders.
{{/usCountry}}India has no dedicated law regulating private detective agencies. But there have been previous court orders.
{{/usCountry}}In the 2000 Navinchandra N Majithia v State of Meghalaya, the Supreme Court held that the Code of Criminal Procedure (now Bharatiya Nagarik Suraksha Sanhita) did not recognise private investigating agencies at all. A person could hire one at their own risk and cost, but the resulting investigation could not be treated as an investigation made under law. The evidence gathered that way cannot be led by a public prosecutor at trial, though the defence was free to rely on it, the order said.
In the Himanshu Chordia case, the bench went into the evidentiary questions around the photographs and videos, and pointed to the requirements that apply to accepting electronic records as evidence.
Drawing on RM Malkani vs State of Maharashtra, it applied a three-fold test for recorded evidence — relevance, identification of the source, and verified accuracy — and noted that certification under Section 65B(4) of the Evidence Act was a mandatory precondition for admitting electronic evidence.
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… One was proposed
The central government introduced the Private Detective Agencies (Regulation) Bill, 2007, proposing a licensing regime with regulatory boards at the central and state levels, and eligibility conditions for agents covering antecedents, training and physical fitness.
According to PRS Legislative Research, agencies would also have had to maintain registers listing managers, staff, clients and the nature of the work they took on, and the Bill carried penalties for agents who violated a person's right to privacy and freedom.
It never became law. PRS records that the Bill was finally withdrawn from the Rajya Sabha on March 23, 2020.
How other countries do it
There is no one model, but most large legal systems license private investigators, set conditions on who may become one and supervise how they work.
The Supreme Court, in its July 31 observation, pointed the Indian legislature towards four of them: Queensland in Australia, Ontario in Canada, the Netherlands and Singapore.
Queensland requires investigators to be fingerprinted, submit to criminal-history checks and complete competency training before they can hold a licence.
Ontario licenses twice over, under its ministry of the solicitor general. Field operatives need one credential, the agencies that employ them another.
Singapore issues both individual and corporate licences through the Singapore Police Force, with background checks, training and periodic renewals.
In the Netherlands, a detective agency needs a permit from the ministry of justice and security, and must comply with the Private Security Organisations and Detective Agencies Act, the accompanying regulations and the sector's privacy code of conduct.
The US licenses at state level — California's Bureau of Security and Investigative Services, for instance, requires applicants to pass a state examination and log 6,000 hours of paid investigative work. American civil courts routinely admit privately obtained photographs, and other laws bar wiretapping and obtaining someone’s bank records under false pretence. Rules on GPS tracking are set state by state, and vary.
In the European Union, the General Data Protection Regulation and Article 8 of the European Convention on Human Rights set the limits. An investigator needs a lawful basis, usually a narrowly defined legitimate interest, before gathering personal data. Some member states add a licensing layer on top. In France, private investigators must hold an authorisation from the National Council for Private Security Activities, and practising without one is a criminal offence.
China banned private detective agencies in 1993, when it barred authorities from registering them as businesses, and private intelligence work is only legal when registered as corporate due diligence or risk management.
Japan regulates the industry through its Detective Business Act. An agency does not need a licence, only a notification filed with the prefectural public safety commission through a local police station. Japanese investigators' own trade bodies have argued for years that licensing and qualifying examinations should be added. A 2025 revision to Japan's anti-stalking law now lets police order detectives to stop supplying information to clients suspected of stalking.
What happens next
Unlike Holmes and Poirot, modern investigators can work off a large digital trail. Social-media posts give away information on relationships, locations and routines. Photographs and videos can be copied and circulated. Digital files carry information about where they came from and who handled them. And increasingly sophisticated editing and generative technologies have made the question of whether an image shows what it claims to show more difficult to authenticate.
But any legal framework will have to come through the legislature. The Supreme Court, for now, has directed that its July judgment be sent to the Law Commission and the law ministry.