Can anyone become a private investigator? No: requirements, licensing, and why unlicensed practice also harms the client
Popular imagination can still give the impression that being an investigator is a matter of buying a camera, launching a website, and starting to investigate.
In Spain, exactly the opposite is true.
Private investigator is a legally reserved profession.
Knowing how to investigate is not enough. Having been a police officer is not enough. Experience in security, intelligence, IT, or OSINT is not enough. And calling yourself a "private investigator," "commercial investigator," or "information agency" is not enough either.
To perform the functions the law reserves to the investigator, one must meet training and good-standing requirements, obtain a licence from the Ministry of the Interior, and practise within an agency subject to the regime of the Private Security Act (Law 5/2014).
And this should matter, above all, to whoever is about to hire one.
First filter: training
Law 5/2014 provides two training routes for investigators: a university degree in the field of private investigation certifying the required competencies, or a certificate from a private investigation course recognised by the Ministry of the Interior.
Training regulations have traditionally shaped these studies as specific, extensive preparation. This is not a short investigation course.
The investigator needs to know how to obtain information, but above all what information can be lawfully obtained and how to turn it afterwards into evidence.
Second filter: personal requirements
Article 28 requires, among other conditions, being of legal age, having physical capacity and psychological fitness, having no criminal record for intentional offences, not having been sanctioned within certain periods for serious or very serious private-security infringements, not having been discharged from the Security Forces and Corps or the Armed Forces in the preceding two years, and not having been convicted in the preceding five years for certain unlawful interferences with fundamental rights.
This last requirement is especially telling. The profession allows aspects of other people's lives to be legitimately investigated; precisely for that reason, the legislator demands special guarantees from whoever is going to practise it.
Third filter: state licensing
It is the responsibility of the Directorate-General of Police to license private investigators and issue the Professional Identity Card, the TIP.
The TIP is not a corporate card or an association's accreditation. It is the identification of legally licensed private security personnel.
Furthermore, the licence is not obtained forever, regardless of what happens afterwards. Losing any of the necessary requirements can bring about its termination and the cancellation of the corresponding registration.
The licence is obtained once. The conditions for keeping it must be met every day.
Having a TIP isn't enough: there's also the agency
In Spain, the investigator practises professionally through private investigation agencies.
The agency must meet its own requirements, file the corresponding statement of responsible declaration, be entered in the competent register, have registered premises, keep a register book, preserve files and reports, hold civil liability insurance, and report the investigators attached to it.
Therefore, when a client commissions an investigation, there are two levels of guarantee: the licensed investigator and the legally constituted agency through which the service is provided.
A profession subject to oversight
A contract must be drawn up for each service. Every assignment is recorded in the register book. A file must exist. A report must be produced. Documentation and supporting material are preserved in accordance with the law. Agencies submit an annual activity report. And investigators must respond to requests from authorities and courts.
If a report is submitted in proceedings, the professional can be summoned to personally ratify its content.
All of this distinguishes a regulated professional activity from someone who simply decides to take up investigating.
The investigator answers for their work
The investigator does not hand over anonymous information. They sign a report, identify the parties involved, describe the actions taken, preserve the supporting material, and may have to sit years later before a judge.
When they take a photograph, they must think not only "have I got the image?" but also "where did I obtain it from? was the position lawful? will I be able to explain how this observation happened? can I prove that this file corresponds to that particular action?"
The licence is not merely a door to walk through. It is the beginning of a responsibility.
The Supreme Court: private investigation is reserved to the licensed investigator
The Third Chamber of the Supreme Court, in its ruling of 19 February 2008, examined the claim by the so-called "commercial and business investigators" to have a separate professional field of their own.
The answer was clear: the legislator had chosen to unify private investigation in the figure of the private investigator.
Changing the name of the activity does not change its nature. If the functions reserved by law are materially being performed, calling them "verification," "personal intelligence," or an "information agency" does not remove the legal requirements.
And what about someone who investigates without a licence?
The Private Security Act treats performing private security functions for third parties without the necessary licence as a very serious infringement.
And, depending on the circumstances, carrying out acts proper to a profession without holding the required qualification can also amount to the offence of unauthorised practice of a profession under Article 403 of the Criminal Code.
There is case law applied to bogus investigators. The ATS 170/2014, of 20 February, upheld a case in which genuine investigator functions had been carried out without the necessary qualification, involving tailing, surveillance, and investigations into the personal lives of third parties.
A distinction should be drawn between a criminal offence and an administrative infringement: not every administrative irregularity automatically amounts to a crime. But from the standpoint of the Private Security Act, performing reserved functions without a licence constitutes a very serious infringement.
The client can also be held liable
Law 5/2014 does not only penalise the impostor. It also provides for the liability of the client who knowingly hires them.
Article 59 classifies as a very serious infringement the hiring or use, with knowledge of the irregularity, of services from agencies lacking the required statement of responsible declaration or from unlicensed individuals.
Very serious infringements by users can carry fines of between 20,001 and 100,000 euros.
"I was only the client" is not always an excuse that works.
And what happens to the evidence?
It is not legally correct to claim that any information obtained by an unlicensed person is automatically voided for that reason alone.
The unlawful practice of a profession is one thing; the constitutional unlawfulness of evidence is another; and its procedural assessment is yet another.
But the client who uses an impostor gives up something fundamental: they are not commissioning the report that the LEC specifically recognises for legally licensed private investigation professionals.
Article 265.1.5 speaks precisely of those professionals.
How to check who you're hiring
Ask for the TIP and the licence number. Check that the service is provided through a legally registered agency. And insist on a properly documented investigation contract.
There is also a very simple warning sign: someone promising what a professional investigator knows they cannot do.
"We listen to their calls." "We get into their email." "You don't need to explain your interest to me." "This isn't recorded anywhere."
When someone presents an illegal act as a selling point, the client should end the meeting.
A good investigator is not the professional who promises to do everything. It is the professional who knows how to lawfully obtain what the client needs to prove.
Conclusion: a profession reserved for a reason
Can anyone be a private investigator in Spain? No.
There is specific training. Access requirements. State licensing. Professional identification. Agencies subject to registration and oversight. Contracts. A register book. Regulated reports. Preservation of evidence. Inspection and liability.
And, finally, there is a professional who signs what they have investigated and personally answers for it before a court.
Hiring a licensed investigator is not paying to get information. It is commissioning a professional investigation capable of becoming evidence.
Truth has a method.